Gordon, whose previous high was 41 points on Jan. 2 against Phoenix, sparked a frantic fourth-quarter rally for the Bulls as they overcame an 18-point deficit.
Gordon had 20 points in the quarter, and Luol Deng added 27 points for the Bulls.
In the overtime, Redd hit a driving layup with 39.7 seconds remaining to cut the Bulls' lead to 122-120.
Milwaukee's Mo Williams lost the handle on the ball as he drove to the basket with 17.8 seconds remaining, and Kirk Hinrich hit four free throws in the final 11.2 seconds remaining to put the game away.
Redd's 52 points is his second-highest total this season, behind the franchise-record 57 he scored Nov. 10 against Utah, also a loss. It is the fourth-highest total in Bucks' history. Ruben Patterson added 17 points for the Bucks (22-38).
The Bulls overcame an 18-point deficit in the fourth quarter to grab their first lead of the game when Gordon drove around a pick and hit a 15-foot jumper with 11.6 seconds remaining in regulation to give the Bulls a 111-110 lead.
Redd then missed from the corner, but Patterson grabbed the rebound and was fouled. He hit one of two free throws with 3.4 seconds remaining to tie it at 111. Chris Duhon missed a desperation half-court shot at the buzzer.
Gordon made 18 of 32 shots, including six 3-pointers. He took over the game in the second quarter with 15 points to keep the Bulls close and then added 20 points in the fourth quarter, mostly on outside shots.
Redd also made 18 of 32 shots, including eight of 13 3-pointers. In the third quarter, Redd shot 8-of-11, including 5-of-6 on 3-pointers.