Dragons (16) 23
Tries: Gomer-Davies, Smith Cons: Alridge, Tovey Pens: Alridge 2 Drop-goal: Alridge
Gloucester (10) 32
Tries: Qera 3, penalty Cons: Robinson 3 Pens: Robinson 2
Flanker Qera scores for Gloucester at Rodney Parade
Akapusi Qera scored a hat-trick as Gloucester ended their Heineken Cup campaign with the bonus-point win that ensures a place in the Challenge Cup.
The hosts were 16-10 ahead at the break, Jamie Alridge kicking 11 points.
But Gloucester stormed clear after the break, Qera scoring his second and third tries and a penalty try completing the bonus-point victory.
Gloucester ended runners-up in their pool and they progress into the last eight of the second tier Challenge Cup.
It was the visitors who made the strong early running, with Nicky Robinson's penalty and Qera's try putting them 10-3 ahead.
But Gloucester lock Dave Attwood was sin-binned for illegally hampering Dragons possession while Olly Morgan had to go off injured and the hosts responded with 13 unanswered points.
Gloucester hit back with Qera scoring just after the restart from an Attwood catch and drive from a line-out.
Qera added a third on 65 minutes after being played in by substitute hooker Olivier Azam from another well-worked set piece.
The fourth try came when referee Christophe Berdos awarded a penalty try as the Dragons failed to contain a Gloucester scrum and flanker Dan Lydiate kicked the ball away.
Ashley Smith scored a late consolation in the last move of the match but it was not enough to prevent the Dragons slumping to their sixth successive defeat in all competitions.
Gloucester head coach Bryan Redpath:
"There was a quarter-final place at stake today, and it is a big thing. It was a big match for us. A European quarter-final gives us something to look forward to.
"We haven't had a great record away from home, and we were aware of that. We got the four tries that we needed."
Redpath on Qera:
"He is a talent, a handful when he plays like that. It is great to see him back from injury.
"I was frustrated with our first-half performance - we did not look energised - but we were a lot stronger in the second period, particularly the forwards. To score four tries away from home is a good return."
Dragons head coach Paul Turner:
"All in all, we made too many errors. The error-count allowed Gloucester too much momentum, and we conceded points.
"We have got to show a bit more resolve when the going gets tough. If you make a couple of mistakes, then good sides tend to punish you.
"I was quite confident going into the game - Gloucester are not a great away team - but it is tough when you start the second half like we started it."
Newport Gwent Dragons: M Thomas; Brew, Gomer-Davies, Riley, Fussell; Arlidge, W Evans; Gustafson, Willis, Robinson, MacDonald, Sidoli, Lydiate, Harris, L Evans.
Replacements: Smith for Gomer-Davies (45), Tovey for Arlidge (66), Leadbeater for W Evans (55), McKenzie for Gustafson (21), S Jones for Willis (64), Castle for Robinson (49), A Jones for MacDonald (64), G Thomas for L Evans (41).
Sin Bin: Castle (55).
Gloucester: Morgan; Simpson-Daniel, Molenaar, Fuimaono-Sapolu, Voyce; Robinson, R Lawson, Dickinson, S Lawson, Somerville, Attwood, Brown, Narraway, Qera, Delve.
Replacements: Sharples for Morgan (29), Burns for Robinson (78), Lewis for R Lawson (65), Wood for Dickinson (55), Azam for S Lawson (60), Capdevielle for Somerville (70), Eustace for Attwood (70), Buxton for Delve (65).
Sin Bin: Attwood (26).
Ref: Christophe Berdos (France).