Steelers quarterback Ben Roethlisberger threw an 8-yard TD pass to Hines Ward just before halftime and his team needed it. Big Ben had already thrown two interceptions, and both led to Green Bay touchdowns.
Green Bay, which deferred after winning the coin toss at the beginning of the game, gets the ball to start the second half.
Rodgers' second TD pass was a 21-yarder to Greg Jennings with 2:31 left in the first half to make it 21-3. That score came four plays after Jarrett Bush set the Packers up with an interception near midfield.
The Steelers then went 77 yards in seven plays, the last two passes to Ward — for 17 yards and then the 8-yard touchdown when he made a leaping two-handed catch in the back of the end zone.
Nick Collins returned the other interception thrown by Roethlisberger 37 yards for a touchdown.
Rodgers threw a 29-yard touchdown pass to Jordy Nelson with 3:44 left in the first quarter. That drive ended with a perfectly placed pass to Nelson, who had made a leaping catch with defender William Gay running with him down the right sideline near the end zone.
The Packers then kicked off and the Steelers started at their own 7 after a holding penalty on the return. On the first snap after that, Roethlisberger was under pressure when he threw. The ball floated and Collins intercepted it.
Green Bay is trying to win its fourth Super Bowl championship. The Steelers are going for the third in six seasons and seventh overall.
Rodgers was 11-of-16 passing at halftime. Roethlisberger was 13 of 21 for 143 yards.
The 45th Super Bowl, the NFL's signature event, pitted two of its storied franchises and capped a season that saw the league reach new heights of popularity despite a string of off-field incidents and that potential lockout with the current collective bargaining agreement expiring in 3 1/2 weeks.
The championship game Sunday also put the focus back on the field after a long, cold week in North Texas that included two wintry storms with snow and ice. There were no weather woes inside $1.2 billion Cowboys Stadium, and it wasn't bad outside either on game day.
Rain started falling after sunset and the NFL was also scrambling to seat 1,250 people whose temporary seats weren't ready by kickoff.