Two tries from Luke McGrath and one by Jordan Larmour saw Leinster beat Ulster 25-10 in the Guinness PRO14 interprovincial derby.
Ross Byrne kicked a conversion and two penalties as the southern province racked up their third successive PRO14 victory -- a fifth overall including their two European Champions Cup games -- with replacement Cathal Marsh also slotting a conversion.
Leinster led 13-10 at the break with Ulster -- who lost heavily in Europe at La Rochelle in their previous game -- failing to add any points after Sean Reidy's 27th-minute try and Christian Lealiifano's conversion on the night when Ireland skipper Rory Best played his 200th game for the northern province.
The four points saw Leo Cullen's squad taste victory for the first time in Belfast since 2014 and meant that their hosts fell to their first home reverse in the league in a year.
Leinster, with recent Lions Jack McGrath, Tadhg Furlong and skipper Sean O'Brien in their starting line-up but without Jonathan Sexton and Robbie Henshaw, were far more accurate and potent throughout to inflict Ulster's second defeat in the league this season, following last month's shock reverse at Zebre.
Lealiifano opened Ulster's account with a sixth-minute wind-assisted penalty but Leinster hit back on the quarter-hour mark when Larmour, a second-minute replacement for Noel Reid at centre, stepped inside Iain Henderson and Aaron Cairns to score near the posts.
Byrne added the conversion and Leinster led 7-3 but the home side roared back to regain the lead when Reidy powered over from a five-metre scrum in the 27th minute after Cairns had been held up over the visitors' line.
Lealiifano's conversion put Ulster 10-7 up but two Byrne penalties made it 13-10 to the visitors at the break.
Leinster had the first scoring chance of the new half, two minutes in, when they swept downfield only for Jamison Gibson-Park's final pass to Dave Kearney to miss the target.
Now with the breeze, Byrne went for the posts from long range after Ulster were penalised at a scrum but the ball sailed wide to the right.
But a minute before the hour, Leinster struck for their second try. Rodney Ah You spilled a ball and the visitors moved the ball at pace out to the right wing.
O'Brien dummied and straightened before giving Luke McGrath the scoring pass to dot down in the corner, with Byrne failing to convert from a difficult angle.
Then with two minutes remaining, McGrath wriggled through the tackles of Ulster substitutes Louis Ludik and Rob Herring to score under the posts with Marsh adding the two points.