The Irish province, which has won six of its last seven RaboDirect PRO12 clashes, ran out comfortable 35-3 winners against Benetton Treviso in Italy.
The result came courtesy of tries for Luke Marshall, Craig Gilroy, Robbie Diack and Jared Payne, as Ireland fly-half Paddy Jackson added 15 points with the boot.
Munster also top their pool, after a nail-biting 18-17 win against Perpignan saw them return from France with four points.
The hosts looked to have won it, with a 77th minute try for Tommaso Benvenuti, but Munster replacement JJ Hanrahan touched down for a dramatic winner.
Also in Pool 6 Edinburgh overturned last weekend's defeat to Gloucester, as they travelled to Kingsholm and emerged 16-10 victors.
The win, which was secured by Ben Atiga's second-half try, sees the Scottish side move into third and within one point of the Cherry & Whites with two games left to play.
Connacht could not repeat last weekend's famous win in Toulouse, as the French giants bounced back to beat Pat Lam's RaboDirect PRO12 minnows 37-9.
Dan Parks kicked three penalties for the hosts but Toulouse proved too powerful, running in five tries to dent Connacht's qualification hopes.
And Leinster failed to complete a double over Northampton Saints as Wales wing George North scored in an 18-9 victory for the Aviva Premiership visitors.
Elsewhere Cardiff Blues edged a low-scoring tie at Glasgow Warriors, winning 9-7, while fellow Welsh outfit Scarlets lost 31-13 to Clermont Auvergne.
Ospreys kept their slim qualification hopes alive as Dan Biggar kicked them to a 21-12 win against Castres Olympique, while Zebre slumped to a 64-3 defeat at Saracens.
And Newport Gwent Dragons lost 32-13 defeat at Bordeaux-Begles in the Amlin Challenge Cup, as Pool 4 tightened up.
TRY OF THE WEEKEND
After Alan Solomons warned of resting his international stars for this match, the task of reversing the previous weekend's defeat to Gloucester looked a stiff one for Edinburgh.
However, the Scottish outfit put in a determined performance and it was capped off by an excellent team effort for their only try of the game.
Edinburgh worked the ball through the phases and deep into the home 22 before launching Kiwi centre Ben Atiga at the line for a match-winning try.
The score will no doubt continue to boost the confidence of the 30-year-old, who revealed last week he is enjoying life under Solomons.
BREAK OF THE WEEKEND
Perpignan's Tommaso Benvenuti looked to have dealt Munster's hopes of a third Heineken Cup crown a heavy blow when he crossed with less than two minutes remaining.
However, Rob Penney's men kept the ball alive from the restart, with Denis Hurley and Tommy O'Donnell setting up JJ Hanrahan to land the final blow.
With the clock already in the red, Hanrahan produced a stunning sidestep from 25 metres out to touch down out wide and hand the 2006 and 2008 champions a third win in four pool games.
PLAY OF THE WEEKEND
Cardiff Blues started their match in Glasgow with a substantial breeze behind them and Rhys Patchell took advantage by landing one of the longest kicks in living memory after just five minutes.
The youngster stepped up to take on a penalty, preferred to British & Irish Lions kicker Leigh Halfpenny, from the wrong side of his own ten-metre line.
And Patchell, who was switched from fly-half to centre due to his side's mounting injury crisis, sent the effort through the posts - a decisive moment as Cardiff went on to win 9-7.
PLAYER OF THE WEEKEND
As Ulster maintained their victorious record in this year's competition, a number of players put in impressive displays - including full-back Jared Payne.
Payne kicked off Ulster's try-scoring afternoon with a perfectly-weighted chip through to Luke Marshall to touch down shortly before half-time.
The 28-year-old Kiwi was solid in defence, as Treviso managed just one penalty, and was a constant threat going forward.
And he secured the bonus point for Ulster, when Andrew Trimble sent him away out wide for the visitors' fourth try towards the end.
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