The announcement comes with immediate effect after Mario Gotze sealed a 1-0 victory for Germany in extra time against Argentina at the Maracana last Sunday.
The 30-year-old Bayern Munich defender has played 113 times for Germany, scoring five goals.
“It’s the right time for me (after the title),” the player was quoted as telling his agent Roman Grill.
“I made the decision that the World Cup in Brazil would be my final tournament,” Lahm said.
Lahm said that he was leaving “in perfect harmony” with the German Football Federation (DFB).
Lahm was the undisputed leader of the German team and a close confidant of coach Joachim Loew during the World Cup.
The full-back, who will continue playing club football for Bundesliga champions Bayern Munich, made his international debut in 2004 against Croatia.
His contract with Bayern runs until 2018.