كتب : Mohamed Sabe
Peruvian striker Claudio Pizarro netted the winner in the second-half to secure Bayern's 13th Cup final victory.
Bayern, who have three games to play in the Bundesliga, are five points clear of Hamburg on the league summit.
If they win the Bundesliga title, the Bavarians will set a precedent by winning back-to-back doubles.
Bayern looked comfortable on the rain-soaked pitch at the Olympiastadion and threatened Frankfurt's goal as early as the 3rd minute.
Pizarro combined with Michael Ballack to set-up Dutch international Roy Makaay who put Frankfurt goalkeeper Oka Nikolov to test with a whipping drive.
Frankfurt held on for the rest of the first-half but couldn't prove match to the Bavarian giants after the break.
Pizarro finally broke the deadlock when he rose to a Ze Roberto corner-kick in the 59th minute to bury home a header past Nikolov.
Frankfurt, with nothing to lose, pushed forward for the equalizer and would have got if it wasn't for a stellar save from Bayern keeper Oliver Kahn.
With three minutes to play, Ioannis Amanatidis made his way into Bayern's area and unleashed a soaring drive that was met by an equally brilliant reflex-save from Kahn that secured the win for the Bavarians.