The footage shows the suspected theft, which happened on 15 November at W H Smith in the Pollet, St Peter Port.
The purse was in a handbag on an unattended baby buggy.
'We are keen to identify the person approaching the rear of the buggy and removing items from the rear pocket,' police said.
Anyone with information is asked to contact to PC115 Liam Blondel or Crimestoppers anonymously on 0800 555 111.
