UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 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)  August 13, 2003

MARKWEST HYDROCARBON, INC.

(Exact name of registrant as specified in its charter)

Delaware	1-11566	84-1352233
(State or other jurisdiction of incorporation or organization)	(Commission File Number)	(I.R.S. Employer Identification Number)
155 Inverness Drive West, Suite 200, Englewood, CO 80112-5000
(Address of principal executive offices)
Registrant’s telephone number, including area code: 303-290-8700

ITEM 7.FINANCIAL STATEMENTS AND EXHIBITS

(c)Exhibits

99.1Press Release dated August 13, 2003

ITEM 12. DISCLOSURE OF RESULTS OF OPERATIONS AND FINANCIAL CONDITION.

On August 13, 2003, MarkWest Hydrocarbon, Inc. (the “Company”) announced its consolidated financial results for the quarter ended June 30, 2003.  A copy of the Company’s earnings press release is furnished as Exhibit 99.1 to this report on Form 8-K.  The information contained in this report on Form 8-K, including Exhibit 99.1, shall not be deemed “filed” with the Securities and Exchange Commission nor incorporated by reference in any registration statement, proxy statement, or other report filed by the Company under the Securities Act of 1933 or the Securities Exchange Act of 1934, unless the Company specifically incorporates that information into those documents by reference.

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SIGNATURES

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

		MARKWEST HYDROCARBON, INC.
		(Registrant)
Date:	August 13, 2003	By:	/s/ Donald C. Heppermann
			Donald C. Heppermann, Senior Vice President, Chief Financial Officer and Secretary

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