Bellingham has made an exceptional start to his Real career but the England international, who also has 10 goals in 11 LaLiga games, suffered a dislocated shoulder in Sunday's scoreless draw with Rayo Vallecano.
That result cost Real their place at the top of the table, with Girona moving two points ahead, and although Bellingham finished the game, he was doubtful for the Braga tie.
"He hasn't done all of the training, to avoid blows, but he's felt good in his movements," Ancelotti told reporters on Tuesday. "He'll probably play tomorrow but I'll evaluate it with him tomorrow."
Real may have lost top spot in Spain but they lead Champions League Group C with three wins and another victory over the Portuguese after last month's 2-1 success away would guarantee qualification with two games to spare.
"It would be important, at this stage of the season, to finish the group stage in four games," Ancelotti said.
"We recently played against Braga, we know each other well and we have to bear in mind that they are a good team that come to the Bernabeu to get points."
Ancelotti also responded to former Barcelona player Carles Puyol, who recently spoke in public about how he would like to talk to Real forward Vinicius Jr about his attitude.
The Brazilian was racially abused during the October 28 Clasico when Real beat Barca 2-1 but the player was also criticised for provoking the crowd after his substitution in that game.
"If Puyol wants to talk to Vinicius, let him talk," Ancelotti said. "He (Vinicius) continues to make a difference. That he has to improve his attitude in some circumstances, that may be, but he has improved a lot and continues to improve."
Ancelotti's side took a 2-0 lead at Braga but the home team pulled one back in the 63rd minute to make for a nervous ending.
"They created a lot of problems for us in the final part of the last game," the Italian said.
"We'll have to defend well, otherwise what happened in the last 30 minutes doesn't happen. Just when we thought it was over, they came back with a lot of fighting."
Real top Group C with nine points followed by Napoli on six, with Braga in third place with three points.
