Aberdeen's Jonathan Hayes opened the scoring after 41 minutes to bring an end to Celtic goalkeeper Fraser Forster's Scottish record for the longest time without conceding a league goal at 1,256 minutes since they beat Aberdeen 3-1 on November 23.
Adam Rooney's diving header put the hosts 2-0 in front just before the break and although Celtic substitute James Forrest pulled a goal back after 62 minutes the home side held on to record a famous victory over the Scottish champions.
Celtic still have a 21-point advantage over second-placed Aberdeen, who have 51 points from 27 games, but manager Neil Lennon was incensed with referee Craig Thomson's performance.
"I think we've been done by the ref," Lennon was quoted as saying by the BBC. "I don't think it's a sending off.
"Then there was a clear handball in the second half that everyone could see, even the referee saw. It's ridiculous."
Aberdeen also knocked holders Celtic out of the Scottish Cup with a 2-1 away win on February 8. Derek McInnes's side had not won at Celtic Park since a Cup quarter-final win in 2008.
(Writing by Ken Ferris; Editing by Ian Ransom)
