He told BBC radio on Friday that he feels better than he has in a decade.
The 62-year-old had suffered from severe weight loss in recent months and has been hospitalized for stomach and colon problems that forced him to curtail public appearances.
He has not specified the exact nature of his illness but told the BBC he had a growth on his colon that was removed.
The singer says his doctors have been amazed by his recovery.
Gibb and his brothers scored many top hits during the disco era.
