Damage was caused to an MG sports car, parked at the rear of The Bargain Centre, Saundersfoot, when a 10-inch scratch was inflicted on the front offside wing.
The incident occurred some time between 5.45 pm on Thursday and 9 am the following day.
Anyone with any information about the incident is asked to contact PC240 Richards at Tenby police station on (01834) 842303.