A man has been airlifted to hospital after colliding with a dolphin while surfing on the New South Wales south coast.

The 27-year-old man was riding a body board at a popular break at Nuggan Point, near Bawley Point, around 9:00am (AEDT) when he was struck by the animal.

Paramedics had to walk 10 minutes to the remote beach where the man had been pulled from the water.

He was taken to Milton Hospital before being airlifted to Sydney's St George Hospital in a stable condition.

He is being treated for lower internal and external injuries to his stomach.

Police are speaking to witnesses at the beach to find out exactly what happened.

NSW Ambulance duty operations manager Wayne Dunlop says incidents like this are not common for paramedics.

"He has come over a wave and as he did so, a dolphin has come through and hit him in the pelvic area," he said.

"The force has been enough to tear the patient's wetsuit."

Inspector Dunlop says that as far as he is aware the dolphin was able to continue on its journey.

The hospital has confirmed today is the man's birthday.