Exhibit 21 BARRETT RESOURCES CORPORATION Subsidiaries of the Registrant Name of Company State of Incorporation - --------------- ---------------------- Bargath, Inc. ............................................ Colorado Barrett 1997 Trust (a business trust) .................... Delaware Barrett Fuels Corporation ................................ Delaware Barrett Resources International Corporation .............. Delaware Barrett Resources (Peru) Corporation ..................... Delaware Grand Valley Gathering System ............................ Colorado Parachute Mountain, Inc. ................................. New Mexico Plains Petroleum Company ................................. Delaware Plains Petroleum Gathering Company ....................... Delaware Plains Petroleum Operating Company ....................... Delaware All of the subsidiaries named above are included in the consolidated financial statements of the Registrant included herein.