Northampton (23) 40
Diggin 2, Hartley, Reihana Pens:
Myler 4 Con:
Myler 2, Everitt 2
Gloucester (19) 22
Wood, James, Foster Pen:
Reihana celebrates going over for Northampton's third try
Northampton produced a stunning display at Franklin's Gardens to deal a severe blow to Gloucester's hopes of reaching the play-offs.
Tries from Paul Diggin and Dylan Hartley helped put Northampton into a narrow 23-19 half-time lead.
The Saints enjoyed the better of the second half, benefitting from Andy Hazell's trip to the sin-bin.
And late scores from Bruce Reihana and Diggin, backed up by Stephen Myler's goalkicking, gave Saints a bonus-point.
Myler, who ended with a haul of 16 points, opened the scoring with a penalty from 35m, while Ryan Lamb hit the post with his attempt to level the scores.
Diggin scored the first of his tries after 10 minutes when he finished off a slick move after good work in the build-up from Lee Dickson and Juandre Kruger.
Gloucester hit back five minutes later when Nick Wood charged down Lee Dickson's clearance kick and dropped on the ball.
Saints' second score came courtesy of some blinding play from Reihana, who stepped past three defenders before linking up with Neil Best who released Hartley on an unopposed run to the line.
Gloucester flanker Akapusi Qera was hauled down just short of the line but the visitors recycled the ball for Will James to stretch over and touch down.
And the visitors claimed a third try when Olly Morgan gave Mark Foster the chance to go through Ben Foden's tackle and score in the corner.
Myler's third penalty gave his side a four-point advantage at the break and Northampton's chances were further improved when Hazell was sin-binned after a flare-up.
A fourth Myler penalty put Saints clear, and Reihana inspired his side to the bonus point - scoring one try himself and putting Diggin away for the fourth try.
Northampton director of rugby Jim Mallinder:
"This year he has been one of our consistent good performers and he was outstanding today.
"He's played a lot at full-back but he's played for the All Blacks on the wing so we know he's equally adept and happy playing there.
"Bruce just has this desire and attitude to be a winner."
Gloucester director of rugby Dean Ryan:
"We lacked any intensity and paid the penalty in the second half for our performance in the first.
"There were times when they opened us up quite easily and we just can't afford to do that away from home.
"We can't come into a league game where the stakes were on for Gloucester and lack that level of intensity."
Foden; Diggin, Ansbro, Downey, Reihana; Myler, Dickson; Tonga'uiha, Hartley, Murray, Lawes, Kruger, Best, S Gray, Wilson.
Mayor for Downey (80), Everitt for Myler (75), Dickens for Dickson (78), Smith for Tonga'uiha (75), Sharman for Hartley (66), Fernandez Lobbe for Lawes (61), Easter for Wilson (71).
Morgan; Foster, Watkins, Allen, Sharples; Lamb, R Lawson; Wood, Azam, Somerville, James, Brown, Strokosch, Qera, Delve.
Barkley for Allen (47), Spencer for Lamb (47), Cooper for R Lawson (73), Nieto for Wood (47), S Lawson for Azam (55), Bortolami for James (70), Hazell for Strokosch (21).
Andrew Small (RFU).