<PAGE>

     As filed with the Securities and Exchange Commission on June 12, 2001

                                                           Registration No. 333-
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                             ----------------------

                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                             ----------------------

                           SIRIUS SATELLITE RADIO INC.
             (Exact name of registrant as specified in its charter)

          Delaware                                            52-170027
(State or other jurisdiction of                             (IRS Employer
incorporation or organization)                            Identification No.)

                     1221 Avenue of the Americas, 36th Floor
                               New York, NY 10020
                                 (212) 584-5100

       (Address, including zip code, and telephone number, including area
               code, of Registrant's principal executive offices)

                 SIRIUS SATELLITE RADIO INC. 401(k) SAVINGS PLAN
                            (Full title of the Plan)

                               Patrick L. Donnelly
              Senior Vice President, General Counsel and Secretary
                           Sirius Satellite Radio Inc.
                           1221 Avenue of the Americas
                                   36th Floor
                            New York, New York 10020
                                 (212) 584-5100
 (Name, address, including zip code, and telephone number, including area code,
                              of agent for service)

                             ----------------------

                                   Copies to:
                                Paul D. Ginsberg
                    Paul, Weiss, Rifkind, Wharton & Garrison
                           1285 Avenue of the Americas
                          New York, New York 10019-6064
                                 (212) 373-3000

                             ----------------------


<TABLE>
<CAPTION>
                                                  CALCULATION OF REGISTRATION FEE
-----------------------------------------------------------------------------------------------------------------------------------
        Title of each class          Amount to be    Proposed maximum offering         Proposed maximum              Amount of
 of securities to be registered(1)  Registered (2)      price per share (3)       aggregate offering price(3)    registration fee
-----------------------------------------------------------------------------------------------------------------------------------
<S>                                     <C>                    <C>                        <C>                          <C>
Shares of Sirius Satellite Radio Inc.
Common Stock, par value $0.001
per share (the "Common Stock")          100,000                $13.66                     $1,366,000                   $342

Preferred Stock Purchase Rights(4)      100,000                 (4)                           (4)                       (4)
-----------------------------------------------------------------------------------------------------------------------------------
</TABLE>

(1)   In addition, pursuant to Rule 416 under the Securities Act of 1933, as
      amended, this registration statement also covers any additional shares of
      Common Stock and Preferred Stock Purchase Rights that may be issuable
      pursuant to the anti-dilution provisions of the employee benefit plan
      described herein.

(2)   This amount represents a 100,000 share increase in the number of shares of
      the Common Stock authorized for issuance under the Sirius Satellite Radio
      Inc. 401(k) Savings Plan.

(3)   The proposed maximum offering price per share and the registration fee
      were calculated in accordance with Rule 457(c) and (h) based on the
      average of the high and low prices for shares of the Common Stock on June
      7, 2001, as reported in the Nasdaq National Market System, which was
      $13.66.

(4)   Each Preferred Stock Purchase Right (the "Rights") represents the
      right to purchase one one-hundredth of a share of Series B Preferred Stock
      for each share of Common Stock. The Rights are appurtenant to and trade
      with the Common Stock. The value attributable to the Rights, if any, is
      reflected in the value of the Common Stock and the registration fee for
      the Rights is included in the fee for the Common Stock.







<PAGE>






                                  INTRODUCTION

         This Registration Statement on Form S-8 is filed by Sirius Satellite
Radio Inc., a Delaware corporation (the "Company"), with respect to an
additional 100,000 shares of the Company's common stock, par value of $0.001 per
share, issuable under the Sirius Satellite Radio Inc. 401(k) Savings Plan (the
"Plan"), and consists of those items required by General Instruction E to Form
S-8.

                                     PART II

                 INFORMATION REQUIRED IN REGISTRATION STATEMENT

Item 3.  Incorporation of Documents by Reference

         The following documents filed by the Company with the Securities and
Exchange Commission (the "Commission") are incorporated herein by reference:

         1.    The Company's Annual Report on Form 10-K for the year ended
               December 31, 2000;

         2.    The Company's Quarterly Report on Form 10-Q for the quarter ended
               March 31, 2001;

         3.    The Company's Registration Statement on Form S-8 (File No.
               333-47954) dated October 13, 2000; and

         4.    The Company's Registration Statement on Form S-8 (File No.
               333-65473) dated October 8, 1998.

         All other documents filed by the Company with the Commission pursuant
to Sections 13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934,
as amended, subsequent to the date of this registration statement and prior to
the filing of a post-effective amendment which indicates that all securities
registered hereby have been sold or which deregisters all securities then
remaining unsold, shall be deemed to be incorporated by reference in this
registration statement and to be part hereof from the date of filing of such
documents. Any statement contained in a document incorporated or deemed to be
incorporated by reference herein shall be deemed to be modified or superseded to
the extent that a statement contained in this registration statement or in any
other subsequently filed document which also is incorporated or deemed to be
incorporated by reference herein modifies or supersedes such statement. Any such
statement so modified or superseded shall not be deemed, except as so modified
or superseded, to constitute a part of this registration statement.

Item 5.  Interests of Named Experts and Counsel

         Patrick L. Donnelly, Esq., whose legal opinion with respect to the
securities registered hereunder is filed as Exhibit 5.1 hereto, is an employee
of the Company and participates in the Plan and other benefit plans established
by the Company.

Item 8.  Exhibits

         See Exhibit Index elsewhere herein.







<PAGE>





                                   SIGNATURES


         Pursuant to the requirements of the Securities Act of 1933, as amended,
the registrant certifies that it has reasonable grounds to believe that it meets
all of the requirements for filing on Form S-8 and has duly caused this
registration statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of New York, State of New York, on June 12, 2001.

                                    SIRIUS SATELLITE RADIO INC.



                                    By: /s/ Patrick L. Donnelly
                                        -------------------------------------
                                        Patrick L. Donnelly
                                        Senior Vice President,
                                        General Counsel and Secretary






<PAGE>






                                POWER OF ATTORNEY

         KNOW ALL MEN BY THESE PRESENTS, that each individual whose signature
appears below hereby constitutes and appoints Patrick L. Donnelly and Douglas
Kaplan, and each of them, his true and lawful agent, proxy and attorney-in-fact,
each acting alone with full power of substitution and resubstitution, for him
and in his name, place and stead, in any and all capacities, to (i) act on, sign
and file with the Commission any and all amendments (including post-effective
amendments) to this registration statement together with all schedules and
exhibits thereto, (ii) act on, sign and file such certificates, instruments,
agreements and other documents as may be necessary or appropriate in connection
therewith, and (iii) take any and all actions which may be necessary or
appropriate in connection therewith, granting unto such agents, proxies and
attorneys-in-fact, and each of them, full power and authority to do and perform
each and every act and thing necessary or appropriate to be done, as fully for
all intents and purposes as he might or could do in person, hereby approving,
ratifying and confirming all that such agents, proxies and attorneys-in-fact,
any of them or any of his or their substitutes may lawfully do or cause to be
done by virtue thereof.

         Pursuant to the requirements of the Securities Act of 1933, as amended,
this registration statement has been signed by the following persons in the
capacities and on the dates indicated:


<TABLE>
<CAPTION>
       Signatures                                 Title                                    Date
       ----------                                 -----                                    ----
<S>                                  <C>                                                 <C>
 /s/ David Margolese                 Chairman and Chief Executive Officer                June 12, 2001
 ------------------------            (Principal Executive Officer)
 David Margolese


 /s/ John J. Scelfo                  Senior Vice President and                           June 12, 2001
 --------------------                Chief Financial Officer
 John J. Scelfo                      (Principal Financial Officer)


 /s/ Edward Weber, Jr.               Vice President and Controller                       June 12, 2001
 ------------------------            (Principal Accounting Officer)
 Edward Weber, Jr.

 /s/ Lawrence F. Gilberti            Director                                            June 12, 2001
 -------------------------
 Lawrence F. Gilberti

 /s/ Joseph V. Vittoria              Director                                            June 12, 2001
 ---------------------------
 Joseph V. Vittoria

</TABLE>







<PAGE>





                                INDEX TO EXHIBITS

<TABLE>
<CAPTION>

EXHIBIT
  NO.
--------
<S>             <C>
5.1             Opinion of Patrick L. Donnelly, Senior Vice President, General Counsel
                and Secretary of the Company (filed herewith).

23.1            Consent of Patrick L. Donnelly, Senior Vice President, General Counsel
                and Secretary of the Company (included in Exhibit 5.1).

23.2            Consent of Arthur Andersen LLP (filed herewith).

</TABLE>
[{"type": "S-8", "sequence": "1", "filename": "a29897.txt", "description": "S-8", "secsgml_size_bytes": 11716}]
{"company-data": {"conformed-name": "SIRIUS SATELLITE RADIO INC", "cik": "0000908937", "assigned-sic": "4832", "irs-number": "521700207", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-62818", "film-number": "1659368"}, "business-address": {"street1": "1221 AVENUE OF THE AMERICAS", "street2": "36TH FLOOR", "city": "NEW YORK", "state": "NY", "zip": "10020", "phone": "2128995000"}, "mail-address": {"street1": "1221 AVENUE OF THE AMERICAS", "street2": "36TH FLOOR", "city": "NEW YORK", "state": "NY", "zip": "10020"}, "former-company": {"former-conformed-name": "CD RADIO INC", "date-changed": "19940203"}}
As filed with the Securities and Exchange Commission on June 12, 2001

                                                           Registration No. 333-
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                             ----------------------

                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                             ----------------------

                           SIRIUS SATELLITE RADIO INC.
             (Exact name of registrant as specified in its charter)

          Delaware                                            52-170027
(State or other jurisdiction of                             (IRS Employer
incorporation or organization)                            Identification No.)

                     1221 Avenue of the Americas, 36th Floor
                               New York, NY 10020
                                 (212) 584-5100

       (Address, including zip code, and telephone number, including area
               code, of Registrant's principal executive offices)

                 SIRIUS SATELLITE RADIO INC. 401(k) SAVINGS PLAN
                            (Full title of the Plan)

                               Patrick L. Donnelly
              Senior Vice President, General Counsel and Secretary
                           Sirius Satellite Radio Inc.
                           1221 Avenue of the Americas
                                   36th Floor
                            New York, New York 10020
                                 (212) 584-5100
 (Name, address, including zip code, and telephone number, including area code,
                              of agent for service)

                             ----------------------

                                   Copies to:
                                Paul D. Ginsberg
                    Paul, Weiss, Rifkind, Wharton & Garrison
                           1285 Avenue of the Americas
                          New York, New York 10019-6064
                                 (212) 373-3000

                             ----------------------
CALCULATION OF REGISTRATION FEE
-----------------------------------------------------------------------------------------------------------------------------------
        Title of each class          Amount to be    Proposed maximum offering         Proposed maximum              Amount of
 of securities to be registered(1)  Registered (2)      price per share (3)       aggregate offering price(3)    registration fee
-----------------------------------------------------------------------------------------------------------------------------------
Shares of Sirius Satellite Radio Inc.
Common Stock, par value $0.001
per share (the "Common Stock")          100,000                $13.66                     $1,366,000                   $342

Preferred Stock Purchase Rights(4)      100,000                 (4)                           (4)                       (4)
-----------------------------------------------------------------------------------------------------------------------------------
(1)   In addition, pursuant to Rule 416 under the Securities Act of 1933, as
      amended, this registration statement also covers any additional shares of
      Common Stock and Preferred Stock Purchase Rights that may be issuable
      pursuant to the anti-dilution provisions of the employee benefit plan
      described herein.

(2)   This amount represents a 100,000 share increase in the number of shares of
      the Common Stock authorized for issuance under the Sirius Satellite Radio
      Inc. 401(k) Savings Plan.

(3)   The proposed maximum offering price per share and the registration fee
      were calculated in accordance with Rule 457(c) and (h) based on the
      average of the high and low prices for shares of the Common Stock on June
      7, 2001, as reported in the Nasdaq National Market System, which was
      $13.66.

(4)   Each Preferred Stock Purchase Right (the "Rights") represents the
      right to purchase one one-hundredth of a share of Series B Preferred Stock
      for each share of Common Stock. The Rights are appurtenant to and trade
      with the Common Stock. The value attributable to the Rights, if any, is
      reflected in the value of the Common Stock and the registration fee for
      the Rights is included in the fee for the Common Stock.
INTRODUCTION

         This Registration Statement on Form S-8 is filed by Sirius Satellite
Radio Inc., a Delaware corporation (the "Company"), with respect to an
additional 100,000 shares of the Company's common stock, par value of $0.001 per
share, issuable under the Sirius Satellite Radio Inc. 401(k) Savings Plan (the
"Plan"), and consists of those items required by General Instruction E to Form
S-8.

                                     PART II

                 INFORMATION REQUIRED IN REGISTRATION STATEMENT

Item 3.  Incorporation of Documents by Reference

         The following documents filed by the Company with the Securities and
Exchange Commission (the "Commission") are incorporated herein by reference:

         1.    The Company's Annual Report on Form 10-K for the year ended
               December 31, 2000;

         2.    The Company's Quarterly Report on Form 10-Q for the quarter ended
               March 31, 2001;

         3.    The Company's Registration Statement on Form S-8 (File No.
               333-47954) dated October 13, 2000; and

         4.    The Company's Registration Statement on Form S-8 (File No.
               333-65473) dated October 8, 1998.

         All other documents filed by the Company with the Commission pursuant
to Sections 13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934,
as amended, subsequent to the date of this registration statement and prior to
the filing of a post-effective amendment which indicates that all securities
registered hereby have been sold or which deregisters all securities then
remaining unsold, shall be deemed to be incorporated by reference in this
registration statement and to be part hereof from the date of filing of such
documents. Any statement contained in a document incorporated or deemed to be
incorporated by reference herein shall be deemed to be modified or superseded to
the extent that a statement contained in this registration statement or in any
other subsequently filed document which also is incorporated or deemed to be
incorporated by reference herein modifies or supersedes such statement. Any such
statement so modified or superseded shall not be deemed, except as so modified
or superseded, to constitute a part of this registration statement.

Item 5.  Interests of Named Experts and Counsel

         Patrick L. Donnelly, Esq., whose legal opinion with respect to the
securities registered hereunder is filed as Exhibit 5.1 hereto, is an employee
of the Company and participates in the Plan and other benefit plans established
by the Company.

Item 8.  Exhibits

         See Exhibit Index elsewhere herein.
SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, as amended,
the registrant certifies that it has reasonable grounds to believe that it meets
all of the requirements for filing on Form S-8 and has duly caused this
registration statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of New York, State of New York, on June 12, 2001.

                                    SIRIUS SATELLITE RADIO INC.

                                    By: /s/ Patrick L. Donnelly
                                        -------------------------------------
                                        Patrick L. Donnelly
                                        Senior Vice President,
                                        General Counsel and Secretary
POWER OF ATTORNEY

         KNOW ALL MEN BY THESE PRESENTS, that each individual whose signature
appears below hereby constitutes and appoints Patrick L. Donnelly and Douglas
Kaplan, and each of them, his true and lawful agent, proxy and attorney-in-fact,
each acting alone with full power of substitution and resubstitution, for him
and in his name, place and stead, in any and all capacities, to (i) act on, sign
and file with the Commission any and all amendments (including post-effective
amendments) to this registration statement together with all schedules and
exhibits thereto, (ii) act on, sign and file such certificates, instruments,
agreements and other documents as may be necessary or appropriate in connection
therewith, and (iii) take any and all actions which may be necessary or
appropriate in connection therewith, granting unto such agents, proxies and
attorneys-in-fact, and each of them, full power and authority to do and perform
each and every act and thing necessary or appropriate to be done, as fully for
all intents and purposes as he might or could do in person, hereby approving,
ratifying and confirming all that such agents, proxies and attorneys-in-fact,
any of them or any of his or their substitutes may lawfully do or cause to be
done by virtue thereof.

         Pursuant to the requirements of the Securities Act of 1933, as amended,
this registration statement has been signed by the following persons in the
capacities and on the dates indicated:
Signatures                                 Title                                    Date
       ----------                                 -----                                    ----
/s/ David Margolese                 Chairman and Chief Executive Officer                June 12, 2001
 ------------------------            (Principal Executive Officer)
 David Margolese

 /s/ John J. Scelfo                  Senior Vice President and                           June 12, 2001
 --------------------                Chief Financial Officer
 John J. Scelfo                      (Principal Financial Officer)

 /s/ Edward Weber, Jr.               Vice President and Controller                       June 12, 2001
 ------------------------            (Principal Accounting Officer)
 Edward Weber, Jr.

 /s/ Lawrence F. Gilberti            Director                                            June 12, 2001
 -------------------------
 Lawrence F. Gilberti

 /s/ Joseph V. Vittoria              Director                                            June 12, 2001
 ---------------------------
 Joseph V. Vittoria
INDEX TO EXHIBITS
EXHIBIT
  NO.
--------
5.1             Opinion of Patrick L. Donnelly, Senior Vice President, General Counsel
                and Secretary of the Company (filed herewith).

23.1            Consent of Patrick L. Donnelly, Senior Vice President, General Counsel
                and Secretary of the Company (included in Exhibit 5.1).

23.2            Consent of Arthur Andersen LLP (filed herewith).