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Exhibit 23

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

        We hereby consent to the incorporation by reference in the Registration Statements listed below of Marathon Oil Corporation of our report dated March 10, 2005, relating to the financial statements, management's assessment of the effectiveness of internal control over financial reporting and the effectiveness of internal control over financial reporting, which appears in this Annual Report on Form 10-K. We also consent to the incorporation by reference of our report dated March 10, 2005, relating to the financial statement schedule, which appears in this Form 10-K.

On Form S-3:			Relating to:
	File No.	33-57997	Dividend Reinvestment Plan
		333-88947	Dividend Reinvestment and Direct Stock Purchase Plan
		333-99223	Marathon Oil Corporation Debt Securities, Common Stock, Preferred Stock, Warrants, Stock Purchase Contracts/Units and Preferred Securities
		333-99223-01	Marathon Financing Trust I
		333-99223-02	Marathon Financing Trust II
On Form S-8:			Relating to:
	File No.	33-41864	1990 Stock Plan
		33-56828	Marathon Oil Company Thrift Plan
		333-29699	1990 Stock Plan
		333-29709	Marathon Oil Company Thrift Plan
		333-52751	1990 Stock Plan
		333-86847	1990 Stock Plan
		333-104910	Marathon Oil Corporation 2003 Incentive Compensation Plan

 
/s/ PricewaterhouseCoopers LLP

PricewaterhouseCoopers LLP
Houston, Texas
March 10, 2005

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Exhibit 23

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM