It happened on Thursday 13 February between 08:25 and 16:25.
The white Hyundai i10 was parked in one of the designated small car spaces at the time of the incident.
The back window was shattered.
Guernsey Police said officers “are seeking information regarding an incident of Criminal Damage to a white Hyundai I10…if anyone has seen this incident or can provide any details in relation to it they are asked to contact the Guernsey Police Headquarters.”
Guernsey Police can be contacted via 725111 or witnesses can call Crimestoppers anonymously on 0800 555 111.
Pictured: The owner found her car window smashed after returning to it at the end of the day.