Aberdeen Coastguard said it had transferred "non-essential" personnel from the Tern Alpha platform more than 100 miles off Shetland.
Four helicopters were involved in the evacuation along with an RAF Nimrod.
The fire broke out in a gas generator on the Shell platform at about 0045 GMT on Thursday. It is believed a high voltage electrical motor overheated.
A total of 65 people remained on board the platform. Shell said all workers had been accounted for.
A coastguard spokesman said the fire had now been extinguished and there were no injuries.
The location of the platform was given as 107 miles north-east of Sumburgh on Shetland.
George Downie, watch manager at Aberdeen Coastguard, said the weather was "relatively good" for rescuers.
A Shell spokeswoman said the police and Health and Safety Executive had been informed of the incident, adding that some of the evacuated workers had been transferred to the company's North Cormorant platform.
March 16, 2006