Sarries' quest to be crowned the best team in Europe for the third time in a row ended in Dublin, where Leinster demonstrated why it has been installed as favourite to lift the trophy.
Garry Ringrose scored an early try and there were further scores from Dan Leavy and James Lowe as Leo Cullen's men raised their game after the break to maintain their 100 per cent record in the competition this season.
Blair Cowan came off the bench to score the holder's only try after Owen Farrell, passed fit after recovering from a quad injury, scored three first-half penalties and Marcelo Bosch added another from long range.
Sarries were second best and their England contingent were unable to gain revenge for a Six Nations defeat at Twickenham that sealed the Grand Slam for Ireland a fortnight ago
Jonathan Sexton scored 13 points with the boot to ensure Leinster will face the Scarlets in the last four as they eye a fourth Champions Cup triumph.
Leinster, roared on by a partisan crowd, made a blistering start and was in front only three minutes in, when Lowe made a break on the left and fed the excellent Isa Nacewa, who passed inside for Ringrose to go under the posts unchallenged.
Sarries responded well to that early blow, applying huge pressure on the Leinster defence and reducing the deficit to only a point courtesy of two Farrell penalties.
Two more Sexton efforts off the tee were then answered, first by Farrell before Bosch was on target with a magnificent kick from halfway in an almighty first-half battle.
Leinster soaked up more Sarries pressure to go in at half-time with a 13-12 advantage after a breathless opening 40 minutes and Sexton's third penalty early in the second half gave them a four-point lead.
The Pro14 side produced another moment of class to leave Saracens up against it, Leavy exchanging passes with James Ryan around the breakdown and finding a gap to score a second try.
Leinster was rampant and Sarries were unable to contain it, Lowe barging his way over with a bit of help from his forwards 58 minutes in and Fergus McFadden adding the extras.
Cowan gave Saracens hope when he dotted down following a catch and drive from a lineout before Devin Toner was sin-binned, but Leinster saw it out comfortably to reach the last four.