Boozer suffered the injury on Saturday during the Bulls' day off. Boozer tripped over a bag in his house and fell.
"[I was] at my house, came around the corner, fell over a bag, put my arm down to kind of brace myself," Boozer said. "I'll get surgery on Tuesday and do my rehab, be conditioned and run with the guys. The good thing about it was at least it only happened in the preseason.
"It's tough. Obviously, I'm disappointed. I feel bad about it, but we got guys who can play, man. Guys will be able to step up and play. We've been practicing hard, getting ready for the preseason right now. I'm going to be there supporting them, I'll be their biggest cheerleader and sideline coach. And I'll be busting my butt trying to get back and healthy and attacking my rehab trying to get right."
The team says Boozer broke the fifth metacarpal bone in his hand. He was evaluated by team physician Dr. Brian Cole and hand specialist Dr. Marc Cohen of Midwest Orthopaedics at Rush.
Said Bulls head coach Tom Thibodeau: "It's part of the NBA. Those things happen. I think we've got more than enough to win with. We're disappointed, obviously, to lose Carlos, who put a lot of work in, and he was playing great, but that's part of the NBA. We move on and we just move forward. We've got plenty of guys who have started and have played in a lot of big games."
In eight professional seasons, Boozer has missed 145 games.
Boozer spent the previous six years with Utah and averaged 19.5 points and 11.2 rebounds last season before joining the Bulls in a sign-and-trade deal with the Jazz.
"It was kind of hard," Gibson said of the circumstances. "Because I came in, I was expecting to just go against him again in practice, just get better, because the whole [experience] was a positive, just learning from him, getting better. Then to come in, see him hurt, hopefully he gets back [as] soon as possible because I know our team's going to need him."
Gibson started 70 games last season, averaging nine points and 7.5 rebounds a game.
Nick Friedell covers the Bulls for ESPNChicago.com and ESPN 1000. Information from The Associated Press contributed to this report.