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): November 9, 2005

MarkWest Hydrocarbon, Inc.
(Exact name of registrant as specified in its chapter)

Delaware	1-14841	84-1352233
(State or other jurisdiction of incorporation or organization)	(Commission File Number)	(IRS Employer Identification No.)

155 Inverness Drive West, Suite 200, Englewood, CO		80112-5000
(Address of principal executive offices)		(Zip code)

Registrant’s telephone number, including area code: 303-290-8700

Not Applicable
(Former name or former address, if changed since last report)

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 (see General Instruction A.2. below):

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

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

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

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

Item 5.02 Appointment of Principal Officers

(c) On November 9, 2005, MarkWest Hydrocarbon’s Board of Directors announced the election of Nancy K. Masten as Senior Vice President and Chief Accounting Officer. Ms. Masten joins MarkWest with a wealth of experience in accounting, taxation, securities law, and management.

Ms. Masten’s responsibilities as Chief Accounting Officer will include all accounting, taxation, and financial reporting functions. Ms. Masten joins MarkWest from Abbott Laboratories, where she had been Chief Financial Officer of Experimental and Applied Sciences, Inc. (EAS), a wholly-owned subsidiary of the Ohio-based Ross Products Division. Prior to joining Abbott Laboratories in 2004, Ms. Masten served as Vice President of Taxation at TransMontaigne, Inc. Before her career in industry, she worked at Ernst & Young for twelve years, most recently as a Tax Partner. She earned a B.S. in Accounting from the University of Kansas and is a licensed CPA in the State of Colorado. In addition to her professional accomplishments, Ms. Masten has served her community as an active volunteer firefighter and Emergency Medical Technician for several years.

A copy of the press release issued on November 9, 2005 is included as exhibit 99.1 to this Form 8-K.

Item 9.01 Financial Statements and Exhibits

Exhibit 99.1

Press Release, dated November 9, 2005, MarkWest Hydrocarbon’s Board of Directors Elects Nancy K. Masten to Chief Accounting Officer

SIGNATURES

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

	MarkWest Hydrocarbon, Inc.
	(Registrant)


Date: November 9, 2005	By:	/s/ James G. Ivey
	Name:		James G. Ivey
	Title:		Chief Financial Officer

Exhibit 99.1

MarkWest Hydrocarbon, Inc.	Contact:	Frank Semple, President & CEO
155 Inverness Drive West, Suite 200		Jim Ivey, SVP & CFO
Englewood, CO 80112-5000		Nancy Masten, SVP & CAO
		Andy Schroeder, VP & Treasurer
(800) 730-8388	Phone:	(303) 290-8700
(303) 290-8700	E-mail:	investorrelations@markwest.com
(303) 290-8769 Fax	Website:	www.markwest.com

MARKWEST HYDROCARBON’S BOARD OF DIRECTORS ELECTS
NANCY K. MASTEN TO CHIEF ACCOUNTING OFFICER

DENVER—November 9, 2005—MarkWest Hydrocarbon, Inc. (AMEX: MWP), (“MarkWest”, or “the Company”) today announces that it has named Nancy K. Masten as Senior Vice President and Chief Accounting Officer. Ms. Masten joins MarkWest with a wealth of experience in accounting, taxation, securities law, and management.

“We are extremely pleased with the addition of Nancy to our senior management team,” said Frank Semple, President and CEO. “Her leadership and experience will be instrumental in enhancing our ability to meet the ongoing accounting, tax, and financial reporting requirements for our rapidly expanding company.”

###

MarkWest Hydrocarbon, Inc. (AMEX: MWP) controls and operates MarkWest Energy Partners, L.P. (AMEX: MWE), a publicly-traded limited partnership engaged in the gathering, processing and transmission of natural gas; the transportation, fractionation and storage of natural gas liquids; and the gathering and transportation of crude oil. We also market natural gas and NGLs.

This press release includes “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. All statements other than statements of historical facts included or incorporated herein may constitute forward-looking statements. Although we believe that the expectations reflected in the forward-looking statements are reasonable, we can give no assurance that such expectations will prove to be correct. The forward-looking statements involve risks and uncertainties that affect our operations, financial performance and other factors as discussed in our filings with the Securities and Exchange Commission (“SEC”). Among the factors that could cause results to differ materially are those risks discussed in our Form 10-K for the year ended December 31, 2003, and our Forms 10-Q for 2004, as filed with the SEC.