|Treviso (7) 20|
|Tries: Christie, Minto Cons: Hayward 2 Pens: Hayward 2|
|Ulster (24) 24|
|Tries: Jackson, Pienaar, Bowe Pen: Jackson Cons: Jackson 3|
Ulster recorded only their second Pro12 away win of the season despite a poor second-half display against Treviso.
The province looked impressive as they raced into a 24-0 lead thanks to tries by backs Paddy Jackson, Ruan Pienaar and Tommy Bowe.
But Ulster failed to secure the bonus point and were ultimately relieved to hang on as Treviso scored 20 points without reply.
Centre Sam Christie and flanker Franceso Minto scored Treviso's tries.
The hosts almost snatched victory when Michele Campagnaro knocked on as he attempted an intercept try.
Ulster, who stay in fifth place in the table, will be disappointed with their second-half showing ahead of their game against European Champions Cup holders Toulon in France on Saturday.
They produced one of their best spells this season to storm into a commanding lead.
The opening try came after just six minutes as fly-half Jackson beat a flat defence by running on to his own grubber kick to score.
Jackson followed his conversion with a penalty and the lead became 17 points when winger Craig Gilroy, back on the pitch after an early sin-binning, drew his man and fed scrum-half Pienaar to run through unchallenged.
There was a question mark over whether Gilroy's final pass was forward but the score was allowed.
Soon it was 24-0 as winger Bowe found a superb line to run on to Jackson's pass inside for the third try of the afternoon.
Treviso responded before the interval, full-back Jayden Hayward kicking skilfully through and centre Christie collecting to score in the corner.
Minto forced over Treviso's second try in the 57th minute after a spell of Ulster pressure, and Hayward landed his second conversion and two penalties as a ragged Ulster lost their way.