EXHIBIT 11
 
                          MARKWEST HYDROCARBON, INC.
                   COMPUTATION OF EARNINGS PER COMMON SHARE
                         (000s, except per share data)

 
 

                                                             For the quarter ended           For the six months ended
                                                                 June 30, 1998                      June 30, 1998
                                                        ------------------------------     ----------------------------
                                                                                      
 
Net income                                                 $                    (1,140)      $                     (223)

Weighted average number of outstanding shares of
     common stock                                                                8,500                            8,498

Basic earnings per share                                   $                     (0.13)      $                    (0.03)
                                                        ==============================     ============================

Net income                                                                      (1,140)                            (223)

Weighted average number of outstanding shares of
     common stock                                                                8,500                            8,498
Dilutive stock options                                                             122                              133
                                                        ------------------------------     ----------------------------
                                                                                 8,622                            8,631

Earnings per share assuming dilution                       $                     (0.13)      $                    (0.03)
                                                        ==============================     ============================