Brooker powered an 88-minute header past Gareth Stewart following Alan Wright's corner and level matters against relegation rivals Bournemouth.
It was a bitter pill to swallow for Bournemouth, who had gone into a two-goal lead through Max Gradel and Marvin Bartley, before David Bird brought Cheltenham back into the game moments before the break.
Searching for a fifth win in eight games as they try and achieve the seemingly impossible mission of reversing their ten-point deduction for going into administration, the home side began with some promise as defender Jason Pearce put a close-range header just wide.
A nervy Cheltenham looked there for the taking and, when Bartley progressed into the area on 16 minutes, he found his path to goal crudely shut off by Craig Armstrong and Gradel calmly converted the penalty.
Bournemouth then very much seized the initiative, bursting forward at every opportunity and went close once more when Lee Bradbury struck the post.
That disappointment quickly subsided as they doubled their lead when Bradbury swung in a dipping cross and Bartley stuck out his right boot to send a looping volley over Shane Higgs for a first career goal.
Their jubilation quickly turned to concern as Kevin Bond's side made the criminal error of conceding just before half-time and allowing Town back into the game.
Brooker made a nuisance of himself, battling with three defenders before the ball broke to Bird and he slotted into the far corner.
The second half continued in its intensity as the game was turning into a real relegation dogfight with chances for either side.
The impressive Jo Kuffour went close twice for the home side, before Steven Gillespie spurned a prime chance for Cheltenham by ignoring the calls of his better-positioned team-mates to shoot from distance.
Somewhat predictably, Bournemouth's failure to close the game out proved their downfall as young legs tired and the seasoned Brooker powered through a static defence for his second goal in as many games.
It was not all rosy for Cheltenham though as they lost substitute Scott Brown in the dying moment to a straight red card, after a nasty confrontation with Bartley inside the centre circle.