Munster were beaten in the Guinness PRO14 final at the RDS on Saturday evening.
The sides were level at 6-6 after 40 minutes as Joey Carbery kicked two penalties for Munster but Leinster were the stronger side after the break.
Leinster started well and earned an early attacking platform off the kick-off and took the lead through a Ross Byrne penalty after three minutes.
Excellent defence from Keith Earls on the wing then kept Leinster out as he forced Rory O’Loughlin to misfire his pass to Jordan Larmour.
Byrne kicked his second penalty on 11 minutes after a second Munster infringement at the breakdown to make it 6-0 to Leinster.
Munster hit back two minutes later through Joey Carbery’s first penalty after Rhys Ruddock went in the side to clear out the impressive Gavin Coombes after a big Jean Kleyn tackle on Cian Healy.
A brilliant one-handed pass from Damien de Allende nearly released Mike Haley down the right wing but the Leinster defence recovered and the chance was gone.
CJ Stander and Gavin Coombes held up Leinster over the line before a Keith Earls intercept brought an end to the attack.
CJ Stander won a breakdown penalty on halfway but Conor Murray’s long-range effort drifted just wide. Coombes then made a break through midfield but Leinster managed to choke tackle Earls on the wing and Leinster regained possession.
Larmour was pinged for not releasing after a Murray tackle but Carbery’s penalty struck the post.
A Jack Conan high tackle on Murray gave Carbery another chance on the stroke of half-time and the out-half made no mistake to level the sides at 6-6.
Leinster made a strong start to the second half, winning a scrum penalty and kicking into Munster territory but the visitors defence did superbly to hold them out.
Jack Conan did get over from close range on 46 minutes as Leinster regained the lead with Byrne’s conversion making it 13-6.
Munster were pinged at the breakdown after 53 minutes but Byrne was off target with the attempt.
Coombes won a massive turnover to halt a Leinster attack on 58 minutes and Munster went on the charge but Ryan Baird dislodged the ball from CJ Stander and the chance was gone.
Byrne made it 16-6 with his third penalty after 68 minutes and that’s how it stayed as Leinster took the title.
In injury news, captain Peter O’Mahony departed after 47 minutes with a deep cut.
Munster: Mike Haley; Andrew Conway, Chris Farrell, Damian de Allende (Rory Scannell, 73), Keith Earls; Joey Carbery (JJ Hanrahan, 68), Conor Murray (Craig Casey, 68); James Cronin (Dave Kilcoyne, 51), Niall Scannell (Kevin O’Byrne, 52), John Ryan (Stephen Archer, 51); Jean Kleyn (Billy Holland, 68), Tadhg Beirne; Gavin Coombes, Peter O’Mahony (C) (inj, Jack O’Donoghue, 47), CJ Stander.