Medical condition behind Byron Bay death
Northern NSW Lifeguard co-ordinator Stephen Leahy said the man, 48, was found in the water between Clarks Beach and The Pass about 8pm on Tuesday.
Passers-by called 000 and tried to resuscitate the man.
Police and ambulance officers continued to try to save the man without success when they arrived soon after.
The section of beach the man was found is generally relatively quiet and Mr Leahy said it was believed the man died as the result of a medical condition.