Great Southern police investigating a string of car thefts and road offences in Mt Barker, Albany and Denmark are on the lookout for a man they believe could assist with the investigation.

Police are appealing to the public for help locating a man they believe could help with their investigation into two vehicle thefts in the past fortnight, posting multiple photos of him online on Tuesday to help the public identify him.

About 11am on August 25, a white Ford Ranger tray top ute with the WA registration PL 12450 was stolen from a property on Riches Road in Mt Barker.

A second ute, a gold Holden Rodeo with the WA registration 1BLC 670, was stolen about 7.50am on Tuesday from a service station on South Coast Highway in Denmark.

Other pieces of personal property, including a skateboard, were also stolen.

Police believe the man could assist them with their investigation into both incidents.

Anyone who can identify the man, has information on his whereabouts, or has any other information that could help the investigation should contact police by calling 1800 333 000 or online at crimestopperswa.com.au.

Albany police are also investigating a third car theft in Orana. A white Nissan Navara ute with registration KE 909 was stolen from a property between August 15 and August 28.

Police do not believe the man is responsible for this incident.