In addition, the Cavs will begin aggressively looking to trade Bynum, sources told ESPN.com.
Cleveland has until Jan. 7 to decide if it will guarantee his contract for the rest of the season. Bynum signed a two-year, $24 million deal with the Cavs last summer, but the team-friendly contract included only $6 million in guaranteed money.
The decision to suspend Bynum was made Friday, sources said. Bynum did not travel with the team to Boston for Saturday's game against the Celtics.
"It's a terrible situation internally with our team," All-Star guard Kyrie Irving said before the Cavs faced the Celtics. "It's something we have to get over."
It is unclear what led to Bynum's suspension. Cavs coach Mike Brown did not disclose any details regarding the suspension but expressed concern for his players.
"I'm worried about the guys in the locker room," Brown said prior to Saturday afternoon's game. "It's simple as that. In our business, there are a lot of ups and a lot of downs throughout the season.
"So what you do as a head coach is keep moving forward. Any time you look back on anything or dwell on anything, is wasted energy from the guys in the locker room, which is obviously very important."
After missing all of last season with knee injuries, Bynum has returned to play in 24 games (19 starts) this season, averaging 8.6 points and 5.3 rebounds while shooting just 42 percent from the floor. But Brown believes that the 26-year-old Bynum, a former All-Star, still can be a high-impact player.
"Yeah, he's a good player," Brown said. "I think everybody saw glimpses of it."
Bynum has admitted on several occasions that he's struggled mentally with learning to play with less mobility and in pain with his knees. Brown also refuted the notion that the 7-foot Bynum doesn't like basketball.
"I've never heard that before," Brown said. "That's something that you'd have to catch up with him and ask."
Because of his flexible contract and that he's proven he can play again, Bynum could have some suitors in the trade market. Brown would not respond when asked if Bynum had played his last game with Cleveland.
Cavaliers spokesman Tad Carper told ESPN.com that the team has canceled a promotional giveaway featuring Bynum.
The Cavaliers had intended to give Bynum Fathead wall decorations to all childen 14 and under at Sunday's home game against the Golden State Warriors. Carper told ESPN.com that the team is working on a replacement plan. Cavaliers owner Dan Gilbert also owns Fathead.
There were times this season Bynum showed flashes of being a dominant post player again. But recently he has lacked energy or enthusiasm, and on Monday he missed all 11 field-goal attempts and didn't score in 22 minutes against Detroit. On Thursday night, Bynum struggled to guard Atlanta's Al Horford and was taken out in the third quarter. Bynum didn't return despite Horford suffering a torn chest muscle in the Hawks' double-overtime win.
Cavs guard Jarrett Jack said Bynum wasn't disruptive and that his quietness may have been misinterpreted.
"That's just kind of how people are sometimes," Jack said. "People like to march to the beat of their own drum. That's not saying you're a bad guy, that's just how you are. I thought we actually had a good relationship with him. He wasn't somebody that was reluctant to speak to people. I thought we had a decent bit of camaraderie and hopefully this will pass and be over and we'll be back at full strength soon."
ESPN.com's Darren Rovell, ESPNBoston.com's Chris Forsberg and The Associated Press contributed to this report.