Police are appealing for witnesses following a collision between a motorcycle and a Ford Focus car at Wartling, north of Pevensey.
The two vehicles, which were travelling in the opposite direction, collided along Wartling Road near Lions Farm at around 12.25pm on Saturday lunchtime.
The motorcyclist, an Eastbourne man in his 40’s, was flown to the Royal Sussex County Hospital in Brighton where he remains in a serious condition. The occupants of the car, a couple in their fifties from Battle, were unhurt.
A Sussex Police spokesman said; “Anyone who saw what happened, or who saw either of the vehicles involved just beforehand, is asked to contact us on 101 quoting Operation Pennock.”