The employees were left "understandably shaken" from their ordeal, police said.
The robbery happened at about 11.45pm yesterday (September 20).
The two men, who were wearing balaclavas, stole cash from a till and cigarettes from a display before running off along the car park at the side of the store, in Crossley Street.
Detective Inspector Dave McDougal, of Leeds District CID, said: “No-one was injured during the incident but the victims were left understandably shaken by what happened.
“We are carrying out extensive enquiries to identify and trace the people responsible and we would like to hear from anyone who was in the area and witnessed anything suspicious or who has any other information that could assist the investigation.”
Anyone with information can contact Leeds District CID via 101 quoting crime reference 13180470761 or call the independent charity Crimestoppers anonymously on 0800 555 111.