CCTV images have been released of the attempted robbery at the Co-op in Evesham Road on Saturday, August 24.
It shows two men who were in the shop at around 4.30pm.
They were wearing masks and carrying a hammer and a knife.
A West Mercia Police Spokesperson said: “They demanded money from the staff.
“Some of the staff were shut in a cupboard during the incident.
“Luckily no one was injured.”
The two men ran towards Kenilworth Close, near the recreation ground and the Pleck – the field behind.
If you have any information contact West Mercia Police on 101 quoting incident 514s of 24 August 2019.
Information can also be provided anonymously by calling independent charity Crimestoppers on 0800 555 111.