© Sean Dempsey / PA Photos
The hosts were ahead from the very first minute when Owen Farrell kicked a penalty and never looked back from that point.
The sides exchanged penalties in the opening 30 minutes, with Ruan Pienaar missing twice before finally kicking three, and the two were each successful again to bring the score to 6-6.
Will Fraser went over the line for the first try of the match on 32 minutes, with Farrell converting to give Saracens a 13-6 lead and after a further penalty they were 10 up at the break.
Farrell kicked another two penalties and Pienaar one before a 62nd-minute Chris Ashton try put Saracens 27-9 ahead.
Ulster rallied late on but a try from Iain Henderson was not enough for them to avoid defeat.