The hosts were set 268 for a spot in the final against the Cobras at Newlands in Cape Town on Friday, but could only manage 209 all out in 44.3 overs in their reply.
JP de Villiers (3/34), Junior Dala (3/35) and Albie Morkel (3/33) all took three wickets each to cap-off a solid performance with the ball from the Titans.
The Dolphins started in the worst possible fashion in their run-chase, falling to 32 for three inside the 10th over.
Only Khaya Zondo with 72 from 87 balls, including five fours and two sixes, offered any real resistance in the Dolphins batting lineup as they were outplayed on the night.
Batting first, the Titans posted a competitive 267 for six in their fifty overs.
The visitors’ efforts with the bat were anchored by Dean Elgar who made 100 from 130 balls, with eight fours and a six after coming to the middle with his side in trouble at eight for two inside three overs.
Opener Jacques Rudolph scrapped out 39 from 69 balls, and together with Elgar the pair put on 78 for the third wicket.
But it was the efforts of David Wiese which changed the game with 71 not out from just 33 balls at a strike rate of 215 at the back end of the Titans innings.
The big-hitting all-rounder struck five fours and five sixes after coming in with his side 159 for five after 40.2 overs.
Elgar was content to give Wiese the strike in the final overs as the duo put on 92 from just 8.5 overs to complete a good outing with the willow for the visitors.