Joachim Low leads Germany into Sunday's showpiece against Argentina as favourites after a ruthless 7-1 destruction of host nation Brazil in the last four.
Lehmann – who won 61 caps for Germany – is confident they will win, citing the large number of Bayern Munich players at Low's disposal as crucial.
The keeper was his nation's penalty shootout hero in their 2006 World Cup quarter-final win against Argentina and Germany beat them at the same stage four years ago.
And Lehmann is convinced Germany will end Argentina's World Cup for the third time in a row.
"I'm sure of it [Germany winning]," Lehmann told FIFA's official website.
"We've got the best team at this World Cup: we're organised, compact and fantastic on the ball.
"You can tell that a lot of our boys, including some of the ones on the bench, are used to playing in the latter stages of the Champions League.
"Germany have got greater strength in depth and we've got more players who play at the highest level every year.
"You only need to look at the kind of big international games the Bayern players have been involved in over the last few years. That makes a huge difference because you gain a lot of experience from those sorts of encounters."
Argentina do have star Lionel Messi at their disposal but according to Lehmann, the forward should prepare himself for a tough encounter.
"He's more than capable of deciding matches on his own, but on Sunday I don't think he'll have it any easier than he did in the semi-final against the Netherlands - if anything it'll be harder for him," he added.
"Messi is outstanding but Germany have got a more complete attack and they'll break down the Argentinian defence, although they might have to be patient."
Lehmann also lavished Germany goalkeeper Manuel Neuer with praise and believes the Bayern man is the best in the world.
"He's had a perfect World Cup so far," he continued.
"He's without doubt the best goalkeeper there is at the moment, and I'm especially pleased about one thing he does.
"Back when I was a player I think I was one of the first keepers to play in the style he's been so successful with today."
