The newly-crowned German champions made a giant stride towards the final in Wembley as they crushed Barcelona at the sold-out Allianz Arena thanks to goals by Thomas Mueller, Mario Gomez and Arjen Robben. It could be Bayern's third Champions League final in four years.
The hosts got their first chance of the game when Javi Martinez set up with his back heel for Arjen Robben, whose low shot on the target was blocked by Barcelona keeper Victor Valdes, Xinhua reports.
Barcelona tried to implement their infamous short passing game yet they were unable to overcome Bayern's well-positioned defence.
Nonetheless it was the hosts who broke the deadlock 25 minutes into the encounter, as Mueller made use of Dante's header following a cross to nod home from very close range at the near post.
Four minutes later Barcelona nearly restored parity but Dante defected the ball before onrushing Lionel Messi had the chance to tap in at the centre of the box.
With the beginning of the second half the visitors quickened the tempo but Bayern continued unfazed to double the lead in the 49th minute when Mario Gomez capitalised on Mueller's header into the centre to slot home following a corner.
Barcelona's Marc Barata had the chance to score while he was unmarked inside the box but he pulled wide.
Dutchmen Arjen Robben made it 3-0 in the 73rd minute when he danced through the visitors defence to beat Valdes with a curl into the far corner.
The Spanish giants were unable to free themselves from their own territory thus Mueller exploited David Alabas low cross into the box to tap in with eight minutes remaining.
Barcelona host Bayern Munich next Wednesday for the second leg.
"It's great to win 4-0 against the best team in the world," said Bayern CEO Karl Heinz Rummenigge.