Bellamy only returned to action at the start of February after three months out, but he was still struggling with the injuries. He went for the operation on Wednesday in a last-ditch effort to save his season.
The Wales international had made only nine appearances for Alan Curbishley's club since his £7.5 million pounds transfer from Liverpool in pre-season.
"We have got some more bad news," Curbishley stated today. "Craig has had an operation on this groin injury and stomach injury that he's had for some time.
"We've been trying all other routes to try and get him fit but in the end we've had to go for the operation.
"He'll be out I think for about six weeks and we hope it's successful. He's had a tough time of it over the last six months."

