The lower house voted 130-0 on Wednesday to approve the text adopted a day earlier by the Senate.
Colombia’s President Juan Manuel Santos said the vote provided "landmark backing" for a deal he personally pushed for. Santos, this year's Nobel Peace Prize winner, shepherded the revised deal through Congress after voters shocked the world by rejecting an earlier version in a referendum last month.
The government's chief peace negotiator with the FARC, Humberto de la Calle, had urged lawmakers to ratify this deal, warning the army's ceasefire with the leftist guerrillas was "fragile".
The first agreement was rejected in a referendum in October, with majority of voters saying they felt it was too lenient toward the rebels, who have battled the government for 52 years.
The peace deal follows three failed efforts to end the conflict, under presidents Belisario Betancur (1982-1986), Cesar Gaviria (1990-1994) and Andres Pastrana (1998-2002).