Leinster took the lead with an early Stephen Grissing try converted by John Sexton before Munster equalised after Denis Hurley and Ciaran O'Boyle to put the impressive James Coughlan over in the right corner.
Leinster should have gone in front after a good Brian Blaney break but the ball was spilled forward in the off-load. That miss was made worse from the restart when O'Boyle raced around his opposite number to run in under the posts, Eoghan Hickey's conversion giving Munster a 14-12 interval lead.
Gary Brown scored the first of his two tries five minutes into the second half (14-19) but Sean Cronin produced his trademark pace to tie the game after good approach work from Coughlan and Shane O'Connor.
O'Connor's second-row partner Billy Holland showed good pace and neat hands when he popped up in support on the right wing to send O'Boyle in for his second try and the game was put well beyond Leinster's reach when replacement Conan Doyle intercepted on his own 22 and showed a clean pair of heels to the blue speedsters who vainly tried to catch him.
Gary Brown scored a consolation try with six minutes remaining but Munster ended the contest on the front foot, attacking in the Leinster 22, their pressure forcing the penalty and Hickey knocking over the penalty.
Munster: M Lawlor (C Doyle); C O'Boyle, P Owens, D Mateus, D Hurley; E Hickey, C Delooze (P Rowley); E McGovern (M Essex), S Cronin, T Buckley (Tim Ryan); S O'Connor, B Holland (M Melbourne); A Quinlan, T McGann (A Kavanagh)(D Sherry), J Coughlan,
Leinster: F Carr; S Grissing, M Berne, F McFadden, G Brown; J Sexton, G Easterby capt; R McCormack, B Blaney, R Sweeney; D Toner, A Byrnes; R Leyden, D Laffan, D Dilllon. Replacements: J Lyne, H Vermass, F Pala'amo, C Culleton, A Dunlop, J Power, A Dunne, C McNaughton.