Exhibit 21.1

MATADOR RESOURCES COMPANY

List of Subsidiaries

As of December 31, 2017

Name	Jurisdiction
Black River Water Management Company, LLC	Texas
Delaware Water Management Company, LLC	Texas
DLK Black River Midstream, LLC	Texas
Fulcrum Delaware Water Resources, LLC	Texas
Longwood Gathering and Disposal Systems GP, Inc.	Texas
Longwood Gathering and Disposal Systems, LP	Texas
Longwood Midstream Delaware, LLC	Texas
Longwood Midstream Holdings, LLC	Texas
Longwood Midstream Southeast, LLC	Texas
Longwood Midstream South Texas, LLC	Texas
Longwood RB Pipeline, LLC	Texas
Longwood Wolf Pipeline, LLC	Texas
Matador Production Company	Texas
MRC Delaware Resources, LLC	Texas
MRC Energy Company	Texas
MRC Energy Southeast Company, LLC	Texas
MRC Energy South Texas Company, LLC	Texas
MRC Permian Company	Texas
MRC Permian LKE Company, LLC	Texas
MRC Rockies Company	Texas
San Mateo Midstream, LLC	Texas
Southeast Water Management Company, LLC	Texas

Note: Inclusion of an entity on the list of subsidiaries is not a representation that such subsidiary is a significant subsidiary.