The move comes after a man threatened a member of staff at the Scotmid Co-Op store in Crookston Road, Glasgow, at around 4.45pm on May 12.
He then fled along Crookston Road.
The man is described as white, in his mid 20s, about 5ft 10in tall, with dark hair and a thin, gaunt appearance.
He was wearing a cream cap, light coloured cardigan with toggle buttons, black trousers and black trainers.
The thief fled with a three-figure sum of money and cigarettes and was seen running along Hatton Gardens.
The 19-year-old employee was not injured but was left badly shaken by the incident.
Detective Constable Andrew Kinnear of Helen Street CID said: "This was a distressing incident for the young member of staff."
Anyone with information should contact Helen Street Police Office on 0141 532 5400 or Crimestoppers on 0800 555 111 where information can be given anonymously.