In difficult conditions at Musgrave Park, the defending champions took an early lead with Deirbhile Nic a Bháird driving over from close range in the 4th minute.
Stephanie Nunan scored in the corner with 13 minutes gone, before Aoife Doyle and Claire Bennett added tries before the break.
Nicole Cronin converted their 4th score to give the home side a 22-0 lead at the interval.
Ulster were much improved after the break and began to retain possession and string together neat phases of play as they recovered from their first half showing.
A superb flowing backline move soon followed, with a clever inside pass releasing full-back Maeve Liston, who broke for a good 20 yards in midfield and got in behind the Munster defence.
Strong carries by Sadhbh McGrath and Sophie Barrett – who replaced Stacey Sloan at the break – saw Neill Alcorn’s side work their way into the Munster half, and they came close to scoring after the influential Ella Durkan slipped away from the defence and drove into the 22. A couple of quick phases then saw Niamh Marley race clear down the left wing, but she was tackled short of the line.
Ulster were quickly forced back into defensive duties after a Munster break, and valiant efforts from the pack saw them twice hold up the champions, with Keelin Brady decisive on both occasions.
As the second half progressed, Ulster turned to the bench as Kelly McCormill replaced Lucy Thompson, Megan Simpson came on for Fiona Tuite, and Ava Fannin took over from Ilse van Staden.
Rachael McIlroy gave way for Amber Redmond, and Sadhbh McGrath came off with Gemma McCamley entering the game. Nicole Watterson came on for Helen McGhee, Mya Alcorn was replaced by Amanda Morton, before Alcorn returned to the pitch, with Ella Durkan coming off.
Although Ulster worked hard to limit the Munster attack, Bennett scored her second try with 64 on the clock, and Deirbhile Nic a Bháird scored again at the final whistle, with Kate Flannery converting.
Ulster
15-9: Maeve Liston; Fern Wilson; Kelly McCormill; Mya Alcorn; Niamh Marley; Ella Durkan; Rachael McIlroy
1-8: Sadhbh McGrath; Beth Cregan (C); Ilse van Staden; Keelin Brady; Helen McGhee; Brenda Barr; Fiona Tuite; Stacey Sloan
Replacements
Gemma McCamley; Megan Simpson; Ava Fannin; Nicole Watterson; Sophie Barrett; Amber Redmond; Amanda Morton; Lucy Thompson.