A man has handed to police in NSW what he claims to be a severed human penis.

The man, who has not been identified, delivered the alleged member to Toukley police station, in the Central Coast, in a plastic bag this morning, The Daily Telegraph reports.

He said that his neighbour's dog found it at Wattagan's National Park, which is about 60km north-west of Toukley.

"Police called the ambulance service who inspected the contents and agreed it appeared to be some form of tissue matter that could be a penis," a police spokesman said today.

"But we are not positive and it is now being taken to a nearby medical facility to be inspected."

"First we have to establish if it is human and if it is obviously the investigation will widen from there."