The 'Cherry and Whites' stamped their authority on this match from the word go, with inside centre Henry Paul slotting two penalty goals within the first 20 minutes of play for a 6-0 lead, but the visitors did wake up in the final few minutes of the match to put a lot of pressure on their hosts.
Gloucester opened their try-scoring tally just after the half-hour mark when England speedster James Simpson-Daniel got over, with Paul converting, and then found themselves in a more than useful 13-0 lead.
Wasps fly-half Alex King eventually put his side on the scoreboard with a penalty goal in the 34th minute, before strong-running outside centre Fraser Waters got over for a try shortly before the half-time break.
King's conversion saw the visitors trail 13-10 at the break, but the home team never allowed them to get into any sort of rhythm for most of the second stanza – outscoring them 15-3 before Wasps' final try-scoring flurry, which saw them net two late five-pointers.
England Sevens and Under-21 speedster Marcel Garvey opened his side's second-half tally with a try in the 55th minute, but King chipped away three points with a penalty goal less than 10 minutes later.
Gloucester's third try, through flanker Andy Hazell, which was converted by Paul, seemed to knock the stuffing out of the Zurich Premiership champions, as they ran into a comfortable 28-13 lead.
Late tries from Kenny Logan and Mark Denney – of which King converted just one – had the 'Cherry and Whites' nervously glancing at the scoreboard, but they managed to hold out and one could almost sense their relief when Tony Spreadbury sounded the final whistle.
Defeat for Wasps is not the end of the world as they are still 10 points ahead of Gloucester on the Zurich Premiership standings, but if Bath beat Harlequins on Sunday – with a bonus point – the current pace-setters will be assured of qualifying for the 2003/04 Zurich Final at Twickenham on May 29.
That would probably leave Wasps fighting it out with Gloucester – yet again – for a place in the Final against Bath, but in the meantime, the Heineken Cup Finalists will be sweating over the fitness of their star front rower Craig Dowd, who was stretchered from the field with what appeared to be a leg injury.
For Gloucester:Tries: Simpson-Daniel, Garvey, HazellCons: Paul 2Pens: Paul 3
For London Wasps:Try: Waters, Logan, DenneyCons: King 2Pens: King 2