General manager Sam Presti announced Wednesday that Oklahoma City had signed Mohammed to an extension. Terms were not disclosed.
"We are pleased to be able to keep Nazr in the Thunder family," Presti said. "He is a valuable part of our organization both on and off the floor. His professionalism, experience, and on-court play have had a positive impact on our young and evolving roster."
A 13-year NBA veteran, Mohammed averaged 6.9 points and 4.8 rebounds in 24 games after being acquired by the Thunder at the trade deadline. He played mostly as a backup behind starter Kendrick Perkins.
The Thunder now have nine of the 10 players from last season's rotation under contract for next season. Only reserve Daequan Cook isn't signed, and he got a qualifying offer from Oklahoma City this week to make him a restricted free agent and give the Thunder a chance to match any offers he gets from other teams.
Almost the entire roster is set for a return after last season's run to the Western Conference finals.
"We like this team. We're going to stick together and see what we can get out of this," All-Star forward Kevin Durant said. "The team last year, our chemistry was really good as the season went on. We didn't end the way we wanted to but I think we were growing as a group throughout the playoffs and we wanted to stick that thing together.
"We wanted to stick it out. We don't want to make any changes just because we lost 4-1 (to Dallas) in the playoffs."