Police were called to Eastbourne Pier around 4.10pm to a man who had fallen onto the beach.
Ambulance was called and the man was being treated for a serious head injury and he was flown to hospital in a life threatening condition.
The Health and Safety Executive has been informed as the man was working on the pier.
More top news
Tuesday night's weather for the west of the region
Tuesday night's weather for the east of the region
Tuesday afternoon's weather for the west of the region