Seán O'Brien tripled his tally of tries for Connacht as Andy Friend's side claimed a convincing bonus-point win in Perpignan.
O'Brien's two first-half tries and a third from Dave Heffernan set Connacht on their way after Paddy Jackson inspired Perpignan into an early lead, but the Irish province were too strong for their hosts and boosted their hopes of reaching the knockout stages of the Challenge Cup.
Tries from Manu Leiataua and Tima Fainga'anuku early in the second half gave Connacht a tough job to close out the win, but Matt Healy and Cian Kelleher sealed the points with two late efforts.
There was plenty for winless Perpignan to be happy with despite defeat to Connacht at the Sportsground last weekend, and as a result the belief grew during the week that they could be set for a first win of the season.
A couple of early penalties allowed the home side to exert some early pressure on Friend's side, and with Jackson involved in the build-up, full-back Julien Farnoux scored after seven minutes.
Jackson missed the conversion and added a penalty moments later, but he was replaced after a disappointing hour.
It was a slow start from Connacht, but after falling behind they settled well and took control. Seán O'Brien earned his side a penalty which Conor Fitzgerald narrowly missed, but after 20 minutes they got the scored they deserved.
David Horwitz kicked his side into the corner from a penalty, and after they set the maul, O'Brien was the man to get the vital touchdown. Fitzgerald landed a brilliant conversion from the sideline to put one point between the sides.
Perpignan's discipline continued to be a problem and some dissent helped Connacht to eat up some yardage, and after their maul worked so well five minutes earlier, Connacht looked to it again and Heffernan scored their second try as Perpignan's maul defence splintered.
Fitzgerald's conversion put Connacht 14-8 ahead, and worse was to come for the home side when winger Tima Fainga'anuku was sin-binned for a shoulder charge on Kelleher. Despite being a man down, Perpignan went on the attack and turned down a kickable penalty in search of a try, but Connacht held solid.
And six minutes from the break Connacht delivered the sucker punch when Robin Copeland's break and pass found its way to O'Brien who dived over for his second try of the match.
And just before the break Fitzgerald stretched Connacht's lead out to 22-8 when the Perpignan tackler didn't roll away after the tackle.
With a 14-point lead at the interval it looked positive for Connacht, but in a stunning open to the second period Perpignan hit back. Leiataua crossed for the home side straight away, but Jackson couldn't convert again, and then Fainga'anuku made amends for his earlier yellow to score in the corner in the 46th minute, which closed the gap to four points.
Perpignan were totally dominant at that stage, but they shot themselves in the foot just before the hour mark when Adrea Cocagi was sent off after a strike on Healy, but they still closed the gap to a point when Tom Ecochard landed a penalty in the 59th minute.
But Healy sealed the bonus point 12 minutes from time before Cian Kelleher ended Perpignan's hopes three minutes later.
Perpignan - J Farnoux (J Bousquet 68); E Sau, A Cocagi, A Taumoepeau, T Fainga'anuku; P Jackson (E Selponi 60), T Ecochard (S Degmache 67); Q Walcker (K Tougne 72), M Leiataua (C Deligny 72), Y Boutemmani (N Lemaire 59); T Labouteley, Y Vivalda; E Shahn (A Brazo 49), P Reynaud (A Brazo h-t-49 HIA) (J Van Heerden 65), K Chateau.
Connacht - D Leader; C Kelleher, K Joyce, D Horwitz (K Godwin 68), M Healy; C Fitzgerald (J Carty 60), J Mitchell (C Blade 60); P McCabe (M Burke 68), D Heffernan (T McCartney 57), D Robertson-McCoy (C Carey 60); J Cannon, G Thornbury (J Maksymiw 59), S O'Brien (E Masterson 56), J Connolly, R Copeland.
Ref - I Tempest (England)