Sgt. Trevin Freitas said that two men wearing masks entered the store, 2114 W. Grant Line Road, just after the front doors opened at 9 a.m.
The men forced the two store employees into a back room and tied them up. The employees were uninjured and were later able to free themselves and call police.
Freitas said that when officers arrived, the robbers were gone. He said the police were trying to determine what had been taken from the store out of sight of the employees.
Police did not have a description of a getaway vehicle and did not say whether the robbers were armed.