The new deal leaves Taman under contract to the CFL club through the 2015 season.
"By completing this extension we have created continuity within the Riders football operations," Riders president Jim Hopson said in a statement. "We feel Brendan is continuously increasing the talent level of this team and we are excited to move forward under Brendan's direction."
Taman is entering his fourth season as GM and fifth with the Riders. He took over the CFL club's football operations department in November of 2011.
"I am once again grateful for the vote of confidence shown to me by Jim Hopson and the Riders board of directors," said Taman. "I understand and welcome the expectations and responsibilities that go along with having this position.
"My job is to keep moving this team forward and I am confident we have the people in place to do that."