EXHIBIT 21


                          MARKWEST HYDROCARBON,  INC.
                             LIST OF SUBSIDIARIES





                   NAME OF SUBSIDIARY                            TYPE OF ENTITY                        RELATIONSHIP
       -------------------------------------------  ----------------------------------------  ------------------------------
 
                                                                                     
1)     MarkWest Michigan, Inc.                      Colorado Corporation                      Wholly-owned subsidiary
 
2)     West Shore Processing Company LLC            Michigan Limited Liability Company        Wholly-owned subsidiary
 
3)     Basin Pipeline LLC                           Michigan Limited Liability Company        Wholly-owned subsidiary
 
4)     MarkWest Resources, Inc.                     Colorado Corporation                      Wholly-owned subsidiary
 
5)     155 Inverness, Inc.                          Colorado Corporation                      Wholly-owned subsidiary