News of the operation was announced by the Hadassah Hospital which indicated that the surgery "does not mean there is a deterioration in Sharon's health." His condition is still described as "serious but stable, " said spokesman Ron Krummer.
Mr Sharon suffered the stroke on January 4 and has not regained consciousness.
Hospital officials said last week a decision has to be made about whether to move Mr Sharon to a long-term care facility.
Experts agree that his chances of recovery are extremely slim, and with each day he remains in a coma, his chances of regaining consciousness diminish.
TV reports last week said the operation to restore about one-quarter of Mr Sharon's skull, removed during previous surgeries, is necessary to allow his transfer to another facility.
This will be Sharon's eighth operation since he suffered the stroke, including lengthy procedures to stop the bleeding in his brain after the haemorrhagic stroke.
Meanwhile Yediot Aharonot has reported that Israel's cabinet will next week pronounce Mr Sharon permanently incapacitated.
Acting Premier Ehud Olmert, whose Kadima party won Israel's election last week, will be declared head of government at Sunday's cabinet meeting in a decision coming into effect on April 14, it said.