Rodgers hasn't played since suffered a broken collarbone early in Green Bay's game Nov. 4. The Packers have gone 2-3-1 -- winning the last two games -- and are 7-7-1 overall.
Green Bay plays the 8-7 Bears Sunday in Chicago, needing a win to claim the NFC North title and a spot in the playoffs.
"We're preparing for the Chicago Bears with Aaron Rodgers as our starting quarterback," McCarthy confirmed at a news conference Thursday.
"We feel it's time for Aaron to play. We need to go down there and win this game as a team. This is a decision everyone was waiting for."
Rodgers, 30, is a three-time Pro Bowl selection. He was 168-of-251 passing for 2,218 yards and 15 touchdowns with just four interceptions in eight games before he was injured this season.
Matt Flynn played the last five games for the Packers. He's completed 102-of-166 passes for 1,146 yards and seven touchdowns. He also has been intercepted four times.
Rodgers had taken part in team workouts on a limited basis in recent weeks but moved up to practicing with the first-team offense as of Thursday, McCarthy said.