The Oilers said in a statement that the NHL club and Prodigal, the operator of the Barons, mutually agreed to part ways after negotiations on an affiliation extension were unsuccessful.
The Barons have been the Oilers' AHL affiliate since the 2010-11 season.
Oklahoma City is averaging 3,219 fans a game this season, below the AHL average and 26th in the 30-team league.
“The players, coaches and fans of the OKC Barons have been outstanding partners to our organization as our development team affiliate," Oilers Entertainment Group president and chief operating officer Patrick LaForge said in the statement. "The decision to move on from Oklahoma City, although not easy, will open new opportunities for the Oilers organization and our AHL business."