After suffering acute abdominal pains at his home in Oxfordshire, he was taken to John Radcliffe Hospital. His wife, Dwina accompanied him. He was later forced to cancel a scheduled radio appearance on Friday.
Doctors are keeping the star under observation, and Gibb has thanked his fans for their ongoing support.
A post on his website reads, "Robin Gibb, accompanied by his wife Dwina, was taken to the John Radcliffe Hospital, Oxford on Thursday 13th October 2011 to undergo tests for abdominal pain and is being treated for inflammation of the colon."
"He requests that since this is a difficult time for him and his family his privacy be respected. Robin would like to thank all his friends and fans for their good wishes and sends them his love."