An investigation is under way after a fatal incident on the Valaris 121 jackup drilling rig, located around 140 miles east of Aberdeen.
The incident happened early on Friday morning and is being examined by the Health and Safety Executive alongside Police Scotland.
Officers said the death is not being treated as suspicious and a report has been submitted to the Procurator Fiscal.
The worker has been named as Lee Hulse, 32. He had been working on the installation when the incident occurred.
In a statement, Valaris said: “Valaris regrets to inform that a crew member onboard its Valaris 121 (V121) jackup drilling rig sadly died as a result of an incident in the early hours of Friday.
"Their next of kin has been informed and Valaris is offering support to them at this difficult time. All remaining personnel onboard the V121 at the time of the incident have been safely accounted for.”
A Shell spokesperson said: “We are deeply saddened by the death of a crew member on Valaris 121, which was working at our Shearwater platform in the North Sea. We are providing support to Valaris following the incident. Our thoughts are very much with the crew member's family and colleagues.”
A GoFundMe page has been launched to support Mr Hulse’s family.