A 43 year old man from NSW is in custody following an alleged serious assault at Rosny this morning.

Shortly after 7.00am police responded to a report of a suspicious vehicle parked on the walking track adjacent to Rosny Esplanade.

On arrival police found a black Great Wall utility vehicle parked on the track.

A 43 year old Bellerive man was found in the ute with serious but not life threatening injuries, consistent with being struck on the back of the head with a tyre lever.

He was treated at the scene before being taken to the Royal Hobart Hospital for treatment.

The other man, who was taken into custody, was also found in the vehicle.

The vehicle was seized and investigations are continuing, with charges expected to be laid later today.

Both men are known to each other.

Anyone with information, or who saw a black Great Wall utility acting suspiciously overnight, is encouraged to contact Bellerive Police on 131 444 or Crime Stoppers anonymously on 1800 333 000.