Manning, who went 23-of-32 through the air for 277 yards, hooked up with Hakeem Nicks twice on scoring strikes -- including a 72-yard TD play late in the third quarter after the Giants had stopped Atlanta's Matt Ryan on a 4th-and-1 quarterback sneak.
Manning also hit Nicks on a four-yard scoring strike in the first quarter and found Mario Manningham on a 27-yard touchdown to cap the game's scoring.
Nicks finished with six grabs for 115 yards and Brandon Jacobs carried the ball 14 times for 92 yards for the Giants, who won for the fourth time in five games now go on to meet the Green Bay Packers next Sunday in the NFC Divisional Round.
Ryan completed 24-of-41 passes for 199 yards for Atlanta, which could manage only a first-quarter safety in their first-ever post-season meeting with New York.
The Falcons gained only 247 yards of total offense, including 64 rushing yards for the game.