UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                               WASHINGTON DC 20549

                                    FORM 8-K
                                 CURRENT REPORT
                       PURSUANT TO SECTION 13 OR 15(D) OF
                       THE SECURITIES EXCHANGE ACT OF 1934
        DATE OF REPORT (DATE OF EARLIEST EVENT REPORTED): MARCH 29, 2005

                            OREGON STEEL MILLS, INC.
--------------------------------------------------------------------------------
             (Exact name of registrant as specified in its charter)

    DELAWARE                           1-9887               94-0506370
--------------------------------------------------------------------------------
(State or other jurisdiction           (Commission          (IRS Employer
 of incorporation)                      File Number)         Identification No.)


1000 S.W. BROADWAY, SUITE 2200; PORTLAND, OREGON                 97205
--------------------------------------------------------------------------------
(Address of principal executive offices)                         (Zip code)


                                 (503) 223-9228
--------------------------------------------------------------------------------
              (Registrant's telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions:

[ ]  Written communications pursuant to Rule 425 under the Securities Act
     (17 CFR 230.425)

[ ]  Soliciting material pursuant to Rule 14a-12 under the Exchange Act
     (17 CFR 240.14a-12)

[ ]  Pre-commencement communications pursuant to Rule 14d-2(b) under the
     Exchange Act (17 CFR 240.14d-2(b))

[ ]  Pre-commencement communications pursuant to Rule 13e-4 (c) under the
     Exchange Act (17 CFR 240.13e-4 (c)


<PAGE>


SECTION 1 - REGISTRANT'S BUSINESS AND OPERATIONS


ITEM 1.01.   ENTRY INTO A MATERIAL DEFINITIVE AGREEMENT.


LETTER OF CREDIT FACILITY AGREEMENT
-----------------------------------

On March 29, 2005, Oregon Steel Mills, Inc. ("OSM") entered into a Letter of
Credit Facility Agreement ("New Credit Agreement") with U.S. Bank National
Association. The New Credit Agreement replaces the Credit Agreement dated as of
July 12, 2002, as amended (the "Existing Credit Agreement"), with certain
financial institutions, as lenders, GMAC Business Credit LLC, as Co-Managing
Agent for the lenders, and Textron Financial Corporation, as Agent for the
lenders which was due to expire on June 30, 2005. The Existing Credit Agreement
was terminated on March 29, 2005, at which time there were no outstanding
borrowings under the Existing Credit Agreement and letters of credit were cash
collateralized until they are reissued under the New Credit Agreement.

The New Credit Agreement provides for a maximum borrowing of $25.0 million for
the issuance of letters of credit and terminates on March 29, 2006. Under the
New Credit Agreement, OSM agrees to pay an issuance fee of the greater of $100
or the face amount of a letter of credit multiplied by 0.125% and a fee, payable
quarterly in arrears, at a rate of 0.50% per annum of the average aggregate
undrawn face amount of all outstanding letters of credit during the preceding
calendar quarter. The New Credit Agreement contains certain customary covenants
for credit facilities of this type, such as provisions regarding compliance with
laws, taxes, notice to issuers and financial information. The New Credit
Agreement is secured by a cash control account.


ITEM 1.02. TERMINATION OF A MATERIAL DEFINITIVE AGREEMENT.


CREDIT AGREEMENT
----------------

OSM and certain of its subsidiaries, as borrowers, were parties to the Existing
Credit Agreement and on March 29, 2005, the Existing Credit Agreement was
terminated. See Item 1.01 of this Current Report on Form 8-K for a discussion of
the New Credit Agreement.

The Existing Credit Agreement provided for a $65.0 million revolving credit to
expire on June 30, 2005. At December 31, 2004, $5.0 million was restricted under
the Existing Credit Agreement, $14.9 million was restricted under outstanding
letters of credit, and $45.1 million was available for use. Amounts under the
Existing Credit Agreement would bear interest based on either (1) the prime rate
plus a margin ranging from 0.25% to 1.00%, or (2) the adjusted LIBO rate plus a
margin ranging from 2.50% to 3.25%. Unused commitment fees ranged from 0.25% to
0.75%. The margins and unused commitment fees were subject to adjustment within
the ranges discussed above based on a quarterly leverage ratio. The Existing
Credit Agreement contained various restrictive covenants including minimum
consolidated tangible net worth amount, a minimum consolidated earnings before
interest, taxes, depreciation and amortization amount, a minimum fixed charge
coverage ratio, limitations on maximum annual capital and environmental
expenditures, a borrowing availability limitation relating to inventory,
limitations on stockholder dividends, and limitations on incurring new or
additional debt obligations or paying cash dividends other than as allowed by
the Existing Credit Agreement. The Existing Credit Agreement was secured by
accounts receivable, inventory, and certain other assets.

The borrowers did not incur any early termination penalties in connection with
the termination of the Existing Credit Agreement.


CAMROSE PIPE COMPANY
--------------------

As part of the acquisition of the remaining interest in Camrose Pipe Company on
March 30, 2005 (see Item 8.01 of this Current Report on Form 8-K), certain
portions of the following agreements are no longer effective: (1) the Asset
Purchase Agreement dated as of January 2, 1992, by and between Camrose Pipe
Company (a partnership) and Stelco Inc. (filed as exhibit 2.0 to Form 8-K dated
June 30, 1992); and (2) the right of first refusal contained in the Partnership
Agreement dated as of January 2, 1992, by and between Camrose Pipe Company and
Stelcam Holding, Inc. (filed as exhibit 28.0 to Form 8-K dated June 30, 1992.)
The parties did not incur any early termination penalties in connection with the
terminations of these portions of these agreements.


SECTION 2 - FINANCIAL INFORMATION

ITEM 2.03 CREATION OF A DIRECT FINANCIAL OBLIGATION OR AN OBLIGATION UNDER AN
OFF-BALANCE SHEET ARRANGEMENT OF A REGISTRANT.

(A) CREATION OF A DIRECT FINANCIAL OBLIGATION

Information concerning OSM's New Credit Agreement is set forth in Item 1.01 of
this Current Report on Form 8-K, which information is incorporated herein by
reference.

ITEM 2.04 TRIGGERING EVENTS THAT ACCELERATE OR INCREASE A DIRECT FINANCIAL
OBLIGATION OR AN OBLIGATION UNDER AN OFF-BALANCE SHEET ARRANGEMENT.

(A) PREPAYMENT OF A DIRECT FINANCIAL OBLIGATION

Information concerning the termination of the Existing Credit Agreement is set
forth in Items 1.01 and 1.02 of this Current Report on Form 8-K, which
information is incorporated herein by reference.

SECTION 8 - OTHER EVENTS

ITEM 8.01 OTHER EVENTS

CAMROSE PIPE COMPANY
--------------------

On March 30, 2005, OSM through Canadian National Steel Corporation, an indirect
wholly owned subsidiary of OSM, purchased the remaining 40% interest of Camrose
Pipe Company for $22.5 million (Canadian) (BRACKET)approximately 18.5 million
US(BRACKET) payable in cash. In addition, OSM, Stelco, Inc. and Camrose Pipe
Company amended the Supply Agreement under which Stelco is granted a right of
first refusal to supply all but 35,000 tons per year of Camrose's requirements
for steel coil from January 1, 2005 until December 31, 2006. As a result of the
purchase, OSM indirectly owns 100% of Camrose Pipe Corporation and provisions of
certain prior agreements are no longer effective, as set forth in Item 1.02 of
this Current Report on Form 8-K.

On March 31, 2005, OSM issued a press release announcing the closing of the
Camrose transaction. The full text of the release is attached as Exhibit 99.1 to
this Current Report on Form 8-K.


<PAGE>



SECTION 9 - FINANCIAL STATEMENTS AND EXHIBITS


ITEM 9.01  FINANCIAL STATEMENTS AND EXHIBITS.


(c)  Exhibits

EXHIBIT
NUMBER            DESCRIPTION

99.1     Oregon Steel Mills, Inc. Press Release dated March 31, 2005 announcing
         the purchase of the remaining interest in Camrose Pipe Company.


                                   SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.

                            OREGON STEEL MILLS, INC.
--------------------------------------------------------------------------------
                                  (Registrant)



Date:     March 31, 2005                     By: /s/ L. Ray Adams
      ---------------------                     ------------------------------
                                                L. Ray Adams
                                                VP Finance, CFO and Treasurer
                                                (Principal Financial Officer)
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{"company-data": {"conformed-name": "OREGON STEEL MILLS INC", "cik": "0000830260", "assigned-sic": "3312", "irs-number": "940506370", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "001-09887", "film-number": "05725896"}, "business-address": {"street1": "1000 SW BROADWAY", "street2": "STE 2200", "city": "PORTLAND", "state": "OR", "zip": "97205", "phone": "5032405788"}, "mail-address": {"street1": "PO BOX 5368", "city": "PORTLAND", "state": "OR", "zip": "97228"}}
UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                               WASHINGTON DC 20549

                                    FORM 8-K
                                 CURRENT REPORT
                       PURSUANT TO SECTION 13 OR 15(D) OF
                       THE SECURITIES EXCHANGE ACT OF 1934
        DATE OF REPORT (DATE OF EARLIEST EVENT REPORTED): MARCH 29, 2005

                            OREGON STEEL MILLS, INC.
--------------------------------------------------------------------------------
             (Exact name of registrant as specified in its charter)

    DELAWARE                           1-9887               94-0506370
--------------------------------------------------------------------------------
(State or other jurisdiction           (Commission          (IRS Employer
 of incorporation)                      File Number)         Identification No.)

1000 S.W. BROADWAY, SUITE 2200; PORTLAND, OREGON                 97205
--------------------------------------------------------------------------------
(Address of principal executive offices)                         (Zip code)

                                 (503) 223-9228
--------------------------------------------------------------------------------
              (Registrant's telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions:

[ ]  Written communications pursuant to Rule 425 under the Securities Act
     (17 CFR 230.425)

[ ]  Soliciting material pursuant to Rule 14a-12 under the Exchange Act
     (17 CFR 240.14a-12)

[ ]  Pre-commencement communications pursuant to Rule 14d-2(b) under the
     Exchange Act (17 CFR 240.14d-2(b))

[ ]  Pre-commencement communications pursuant to Rule 13e-4 (c) under the
     Exchange Act (17 CFR 240.13e-4 (c)
SECTION 1 - REGISTRANT'S BUSINESS AND OPERATIONS

ITEM 1.01.   ENTRY INTO A MATERIAL DEFINITIVE AGREEMENT.

LETTER OF CREDIT FACILITY AGREEMENT
-----------------------------------

On March 29, 2005, Oregon Steel Mills, Inc. ("OSM") entered into a Letter of
Credit Facility Agreement ("New Credit Agreement") with U.S. Bank National
Association. The New Credit Agreement replaces the Credit Agreement dated as of
July 12, 2002, as amended (the "Existing Credit Agreement"), with certain
financial institutions, as lenders, GMAC Business Credit LLC, as Co-Managing
Agent for the lenders, and Textron Financial Corporation, as Agent for the
lenders which was due to expire on June 30, 2005. The Existing Credit Agreement
was terminated on March 29, 2005, at which time there were no outstanding
borrowings under the Existing Credit Agreement and letters of credit were cash
collateralized until they are reissued under the New Credit Agreement.

The New Credit Agreement provides for a maximum borrowing of $25.0 million for
the issuance of letters of credit and terminates on March 29, 2006. Under the
New Credit Agreement, OSM agrees to pay an issuance fee of the greater of $100
or the face amount of a letter of credit multiplied by 0.125% and a fee, payable
quarterly in arrears, at a rate of 0.50% per annum of the average aggregate
undrawn face amount of all outstanding letters of credit during the preceding
calendar quarter. The New Credit Agreement contains certain customary covenants
for credit facilities of this type, such as provisions regarding compliance with
laws, taxes, notice to issuers and financial information. The New Credit
Agreement is secured by a cash control account.

ITEM 1.02. TERMINATION OF A MATERIAL DEFINITIVE AGREEMENT.

CREDIT AGREEMENT
----------------

OSM and certain of its subsidiaries, as borrowers, were parties to the Existing
Credit Agreement and on March 29, 2005, the Existing Credit Agreement was
terminated. See Item 1.01 of this Current Report on Form 8-K for a discussion of
the New Credit Agreement.

The Existing Credit Agreement provided for a $65.0 million revolving credit to
expire on June 30, 2005. At December 31, 2004, $5.0 million was restricted under
the Existing Credit Agreement, $14.9 million was restricted under outstanding
letters of credit, and $45.1 million was available for use. Amounts under the
Existing Credit Agreement would bear interest based on either (1) the prime rate
plus a margin ranging from 0.25% to 1.00%, or (2) the adjusted LIBO rate plus a
margin ranging from 2.50% to 3.25%. Unused commitment fees ranged from 0.25% to
0.75%. The margins and unused commitment fees were subject to adjustment within
the ranges discussed above based on a quarterly leverage ratio. The Existing
Credit Agreement contained various restrictive covenants including minimum
consolidated tangible net worth amount, a minimum consolidated earnings before
interest, taxes, depreciation and amortization amount, a minimum fixed charge
coverage ratio, limitations on maximum annual capital and environmental
expenditures, a borrowing availability limitation relating to inventory,
limitations on stockholder dividends, and limitations on incurring new or
additional debt obligations or paying cash dividends other than as allowed by
the Existing Credit Agreement. The Existing Credit Agreement was secured by
accounts receivable, inventory, and certain other assets.

The borrowers did not incur any early termination penalties in connection with
the termination of the Existing Credit Agreement.

CAMROSE PIPE COMPANY
--------------------

As part of the acquisition of the remaining interest in Camrose Pipe Company on
March 30, 2005 (see Item 8.01 of this Current Report on Form 8-K), certain
portions of the following agreements are no longer effective: (1) the Asset
Purchase Agreement dated as of January 2, 1992, by and between Camrose Pipe
Company (a partnership) and Stelco Inc. (filed as exhibit 2.0 to Form 8-K dated
June 30, 1992); and (2) the right of first refusal contained in the Partnership
Agreement dated as of January 2, 1992, by and between Camrose Pipe Company and
Stelcam Holding, Inc. (filed as exhibit 28.0 to Form 8-K dated June 30, 1992.)
The parties did not incur any early termination penalties in connection with the
terminations of these portions of these agreements.

SECTION 2 - FINANCIAL INFORMATION

ITEM 2.03 CREATION OF A DIRECT FINANCIAL OBLIGATION OR AN OBLIGATION UNDER AN
OFF-BALANCE SHEET ARRANGEMENT OF A REGISTRANT.

(A) CREATION OF A DIRECT FINANCIAL OBLIGATION

Information concerning OSM's New Credit Agreement is set forth in Item 1.01 of
this Current Report on Form 8-K, which information is incorporated herein by
reference.

ITEM 2.04 TRIGGERING EVENTS THAT ACCELERATE OR INCREASE A DIRECT FINANCIAL
OBLIGATION OR AN OBLIGATION UNDER AN OFF-BALANCE SHEET ARRANGEMENT.

(A) PREPAYMENT OF A DIRECT FINANCIAL OBLIGATION

Information concerning the termination of the Existing Credit Agreement is set
forth in Items 1.01 and 1.02 of this Current Report on Form 8-K, which
information is incorporated herein by reference.

SECTION 8 - OTHER EVENTS

ITEM 8.01 OTHER EVENTS

CAMROSE PIPE COMPANY
--------------------

On March 30, 2005, OSM through Canadian National Steel Corporation, an indirect
wholly owned subsidiary of OSM, purchased the remaining 40% interest of Camrose
Pipe Company for $22.5 million (Canadian) (BRACKET)approximately 18.5 million
US(BRACKET) payable in cash. In addition, OSM, Stelco, Inc. and Camrose Pipe
Company amended the Supply Agreement under which Stelco is granted a right of
first refusal to supply all but 35,000 tons per year of Camrose's requirements
for steel coil from January 1, 2005 until December 31, 2006. As a result of the
purchase, OSM indirectly owns 100% of Camrose Pipe Corporation and provisions of
certain prior agreements are no longer effective, as set forth in Item 1.02 of
this Current Report on Form 8-K.

On March 31, 2005, OSM issued a press release announcing the closing of the
Camrose transaction. The full text of the release is attached as Exhibit 99.1 to
this Current Report on Form 8-K.
SECTION 9 - FINANCIAL STATEMENTS AND EXHIBITS

ITEM 9.01  FINANCIAL STATEMENTS AND EXHIBITS.

(c)  Exhibits

EXHIBIT
NUMBER            DESCRIPTION

99.1     Oregon Steel Mills, Inc. Press Release dated March 31, 2005 announcing
         the purchase of the remaining interest in Camrose Pipe Company.

                                   SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.

                            OREGON STEEL MILLS, INC.
--------------------------------------------------------------------------------
                                  (Registrant)

Date:     March 31, 2005                     By: /s/ L. Ray Adams
      ---------------------                     ------------------------------
                                                L. Ray Adams
                                                VP Finance, CFO and Treasurer
                                                (Principal Financial Officer)