UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 12b-25

NOTIFICATION OF LATE FILING

(Check one):

o Form 10-K

o Form 20-F

o Form 11-K

ý Form 10-Q

o Form N-SAR

o Form N-CSR

For Period Ended:

March 27, 2005

o Transition Report on Form 10-K

o Transition Report on Form 20-F

o Transition Report on Form 11-K

o Transition Report on Form 10-Q

o Transition Report on Form N-SAR

For the Transition Period Ended:

Nothing in this form shall be construed to imply that the Commission has verified any information contained herein.

If the notification relates to a portion of the filing checked above, identify the Item(s) to which the notification relates:

Item 1. Financial Statements, Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations, and Item 4. Controls and Procedures.

PART I — REGISTRANT INFORMATION

Molson Coors Brewing Company Full Name of Registrant

Former Name if Applicable

1555 Notre Dame Street East Montréal, Québec, Canada, H2L 2R5

311 10th Street Golden, Colorado 80401 Address of Principal Executive Offices, Including Zip

PART II — RULES 12b-25(b) AND (c)

If the subject report could not be filed without unreasonable effort or expense and the registrant seeks relief pursuant to Rule 12b-25(b), the following should be completed. (Check box if appropriate)

		(a)		The reason described in reasonable detail in Part III of this form could not be eliminated without unreasonable effort or expense;
ý		(b)		The subject annual report, semi-annual report, transition report on Form 10-K, Form 20-F, Form 11-K, Form N-SAR or Form N-CSR, or portion thereof, will be filed on or before the fifteenth calendar day following the prescribed due date; or the subject quarterly report or transition report on Form 10-Q, or portion thereof, will be filed on or before the fifth calendar day following the prescribed due date; and
		(c)		The accountant's statement or other exhibit required by Rule 12b-25(c) has been attached if applicable.

PART III — NARRATIVE

State below in reasonable detail why Forms 10-K, 20-F, 11-K, 10-Q, N-SAR, N-CSR, or the transition report or portion thereof, could not be filed within the prescribed time period.

        As a result of the closing of the merger with Molson Inc. on February 9, 2005 (the "Merger"), Molson Coors Brewing Company (f/k/a Adolph Coors Company) is unable to file its Quarterly Report on Form 10-Q (the "Quarterly Report") for the quarterly period ended March 27, 2005 within the prescribed time period. Despite considerable effort by the Company, in light of the significant complexities imposed by the Merger, additional time is needed to conclude the Company's analysis of required disclosures, including finalizing balance sheet classifications, resolving the appropriate reporting of the results of the Company's Brazilian business, and allowing a full and complete review of the Quarterly Report by the external auditors.

        The Company expects to file the Quarterly Report on or before May 11, 2005, the fifth calendar day following the prescribed due date for filing the Quarterly Report.

(Attach extra Sheets if Needed)
SEC 1344 (07-03)		Persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.

PART IV — OTHER INFORMATION

(1)		Name and telephone number of person to contact in regard to this notification
		Ronald A. Tryggestad (Name)		(303) (Area Code)		279-6565 (Telephone Number)
(2)		Have all other periodic reports required under Section 13 or 15(d) of the Securities Exchange Act of 1934 or Section 30 of the Investment Company Act of 1940 during the preceding 12 months or for such shorter period that the registrant was required to file such report(s) been filed? If answer is no, identify report(s).
						ý Yes        o No
(3)		Is it anticipated that any significant change in results of operations from the corresponding period for the last fiscal year will be reflected by the earnings statements to be included in the subject report or portion thereof?
						ý Yes        o No
		See Exhibit 99.1.
		If so, attach an explanation of the anticipated change, both narratively and quantitatively, and, if appropriate, state the reasons why a reasonable estimate of the results cannot be made.

Molson Coors Brewing Company (Name of Registrant as Specified in Charter)

has caused this notification to be signed on its behalf by the undersigned hereunto duly authorized.

Date

May 6, 2005

By

/s/  RONALD A. TRYGGESTAD     Ronald A. Tryggestad Vice President and Controller (Chief Accounting Officer)

INSTRUCTION: The form may be signed by an executive officer of the registrant or by any other duly authorized representative. The name and title of the person signing the form shall be typed or printed beneath the signature. If the statement is signed on behalf of the registrant by an authorized representative (other than an executive officer), evidence of the representative's authority to sign on behalf of the registrant shall be filed with the form.

Intentional misstatements or omissions of fact
constitute Federal Criminal Violations
(See 18 U.S.C. 1001).

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