Wade, selected as a starter for the Eastern Conference in the NBA All-Star Game this weekend in Phoenix, scored 24 points. Wade scored eight points in the fourth quarter and passed out of a double-team to find Marion for the decisive dunk.
"It was just a read. I saw the man (Tyrus Thomas) was going to jump out on me as soon as I touched the ball. Shawn did what he does best and that's cut to the basket. He made a great finish," said Wade.
Reserve Michael Beasley finished with 21 points for the Heat, who came in as a loser of five out of the last seven games.
"They ran to him and he ran a play and (Dwyane) came off. I stepped right in and went to the basket to finish it real quick," Marion said.
Ben Gordon finished with 34 points for Chicago.
With Miami trailing 86-85, Wade led an 8-0 run. Mario Chalmers had a reverse layup to give Miami the lead back, then Marion blocked Derrick Rose's shot and finished with a dunk on the other end. Wade made a jumper, then hit a fadeaway over Rose to give the Heat a 93-86 lead with 1:13 left.
But the Bulls came back by scoring seven consecutive points. Thomas' basket got them within 93-90 with 35 seconds left, then Gordon was fouled by Daequan Cook on a 3-point attempt. He hit all three free throws to tie the game at 93 with 6.5 seconds left.
"All we had to do was get the ball in bounds," Gordon said. "It's definitely a heartbreaker when you work that hard to get back in the game and then have a chance to win."
The Heat executed this time when Wade found Marion for an easy dunk.
Chicago had a foul to give, but was unable to use it.
"By the time Shawn Marion got the ball, he was one dribble and at the rim, so it would've been a two-shot foul," Joakim Noah said.
After trailing by 11 to start the fourth quarter, Chicago came back to take the lead. Gordon had a three-point play with 3:54 left to get the Bulls within 85-84. Then Rose gave the Bulls the lead by blowing by Chalmers.
The Heat led by 13 early in the third quarter, but the Bulls cut into the lead.
Beasley, picked No. 2 in this year's draft after Rose, highlighted the third quarter with 13 points on 5-for-5 shooting. He showed his range by hitting a 3 to give the Heat a 74-60 lead with 1:37 left in the period.
"Michael was great tonight," Miami coach Erik Spoelstra said. "Yesterday I had a talk with our three young guys before practice. I talked especially to Michael since he has gotten a lot of criticism lately. We knew there would be ups and downs for every rookie."
Trailing 76-62, the Bulls cut into the Heat lead in the fourth quarter. Andres Nocioni hit a 3 with 4.3 left in the third quarter, then Chicago outscored Miami 10-2 to start the fourth period.
The Heat closed the first half by outscoring the Bulls 10-2. Udonis Haslem and Marion had back-to-back dunks, then Wade had a one-handed reverse layup. Marion gave Miami a 50-39 lead at the half with a jumper.
Marion, Haslem, Wade and Cook all scored eight points in the half for Miami. Gordon led the Bulls with 14 points on 6-of-7 shooting.
- Wade stopped Gordon's breakaway layup attempt with a highlight block late in the first quarter.
- Bulls F Drew Gooden missed his 22nd game of the season with a left groin strain.