Steven Gillespie's fourth goal in five outings sunk Leeds United at a packed Whaddon Road this afternoon.
The young striker's late goal handed manager Keith Downing the first success of his tenure and condemned United to only their second defeat of the season.
Leeds, in fairness, were dominant throughout, created a host of chances and always looked the more likely winners but the commitment and application of this Robins' side carried them to a memorable victory.
Robins' boss Keith Downing made a couple of changes to the side that were defeated by Brighton and Hove Albion in the FA Cup on Tuesday evening.
Dean Sinclair was restored to the side in central midfield having missed the encounter on the South coast, while Ashley Vincent, who picked up a knock at Southend eight days and did not travel for that game, returned on the left.
Mid-week aquisitions Guy Madjo and Michael D'Agostino joined Andy Lindegaard on the bench.
Leeds made a strong challenge in the early exchanges and went close to opening the scoring as early as the fifth minute when Jermaine Beckford played in Tresor Kandol, who blasted wide from 18 yards.
Shane Higgs then fell onto a Sebastian Carole effort from similar range a couple of moments later, while Beckford showed great trickery to lift the ball over Shane Duff inside the area before striking a volley over the top left angle of Higgs' goal.
Cheltenham though weathered the early storm and began to get a foothold in the game at the mid-way point of the first half.
For all of their bluster, Leeds were finding it difficult to carve a way though a compact and resiliant Cheltenham back four, while Dean Sinclair was at the centre of all of the home side's limited attacking play.
His midfield partner David Bird needed to be sharp to clear the danger from a David Prutton free-kick around the half hour mark.
The former Southampton and Nottingham Forest man drilled one through the defensive wall but Bird was on hand to hook it clear under pressure from Carole six yards out.
At the other end, centre half Rui Marques needed to be alert to deny Steven Gillespie ten minutes from the break after a promising move from a corner on the left.
But Leeds underlined their threat a minute later when Douglas teed up Beckford, who clipped the cross bar with a fierce drive from 18 yards.
A clever flick by Kandol released Beckford five minutes after the resumption but the striker, with just Higgs to beat, lifted it over the goalkeeper and into the side netting.
Next, Gillespie was set on his way by Ashley Vincent but his angled effort flashed inches over the target.
Beckford blasted a volley over from close-range after Prutton had done well to deceive Alan Wright on the byline and deliver the ball to the striker at the back post.
A moment later Kandol met an Ian Westlake delivery from the left but his downward header was held onto by Higgs.
United boss Dennis Wise, presumably reacting to his side's wastefulness in front of goal, had made all three of his changes by the 73rd minute, going with three up front with former Norweigan international Tore Andre Flo playing in the hole behind the trio.
They had the ball in the back of the net shortly afterwards, although the effort was ruled out for offside.
Skipper Douglas unleased a fearsome free-kick from 25 yards that Higgs spilled, but Beckford, reacting quickest, had his header chalked off by the Assistant Referee.
Guy Madjo was handed his Cheltenham debut, replacing Paul Connor in the 77th minute and went close with eight minutes remaining.
Higgs launched a huge downfield kick that bounced once before the Cameroonian challenged with goalkeeper Lucas. He missed his clearance and fell awkwardly while Madjo clipped the ball over.
But the unlikely winner came in the 86th minute, and again the Leeds number one was at the centre of the move.
Lindegaard slipped a ball inside to the edge of the penalty area, where the Lucas had rushed from his line to head the ball clear. Fortunately from a Cheltenham perspective, Gillespie was on hand 25 yards from goal to lift the loose ball into the open goal to take the roof off Whaddon Road.
CHELTENHAM TOWN (4-4-2): Higgs; Gill (c), Caines, Duff, Wright; Vincent (Lindegaard 72), Bird, Sinclair, Spencer; Connor (Madjo 77), Gillespie. Subs not used: Brown (Gk), Gallinagh, D'Agostino
LEEDS UNITED (4-4-2): Lucas; Richardson, Marques, Heath, Parker (De Vries 73); Prutton (Flo 73), Douglas (c), Hughes, Carole (Westlake 56); Beckford, Kandol. Subs not used: Huntington, Kishishev.
REFEREE: L.W. Probert (Wiltshire)
ATTENDANCE: 7,043 (1,814) from Leeds