From the off Rochdale pressed but it looked as though the game was heading for stalemate until the dying seconds when leading scorer Adam Le Fondre blasted home from close range for his 19th goal of the season.
For much of the match it was a tale of two goalkeepers with the home side's Marek Stech keeping the visitors at bay time and again whilst at the other end Rochdale's Frank Fielding produced a stunning first half double save from Wycombe's only real opportunity of the game.
Rochdale who now move up to second in the table threatened to over-run their hosts in the first half but a combination of poor finishing and excellent goalkeeping by Stech, on loan from West Ham United, kept them at bay.
It looked like being honours even but deep into time added on substitute Adam Rundle crossed the ball into the box where it was well held up by fellow substitute Gary Madine and Le Fondre arrived with perfect timing to ram the ball home.
Rochdale are now hot on the heels of leaders Brentford whilst Peter Taylor's Wycombe have now dropped out of the top three for the first time this season.