The actor mocked Gibson's drunken driving arrest when he was honored at Spike TV's Guys Choice Awards in Los Angeles on Saturday for his role in "Fight Club," which was inducted into the Guy Hall of Fame, Usmagazine.com reported.
Mel Gibson, who rode in on a horse wearing a Viking helmet, introduced "Fight Club" and handed Pitt the award.
"Thanks, sugar t---!" Pitt said to Gibson, who reportedly referred to a female officer by that name during his 2006 DUI arrest.
Pitt then plugged his own movie, "Inglourious Basterds," and began pumping his fists.
"Thank you for the greatest moment of my f---ing life!" he said to the audience.
Gibson, father of seven, made headlines last week when he announced that girlfriend Oksana Grigorieva was pregnant.
"I guess I'm Octo-Mel," he joked on the "Tonight Show with Jay Leno" last week.
The "Braveheart" actor split with his wife of 28 years after the drunken driving arrest three years ago. She filed for divorce last month.