Police say that just after 9 pm on Tuesday night the men entered the filling station shop on the Beersbridge Road armed with a suspected firearm and demanded money.
It is believed they made off with a sum of cash in the direction of Hyndford Street.
The robbers are thought to be in their late teens or early 20s, of slim build, and around 5ft 8″ or 5ft 9″ tall and both were wearing dark gloves.
One of the men was wearing a black hooded top and black tracksuit bottoms.
The second was wearing a dark grey windbreaker jacket and black tracksuit bottoms.
Anyone with information is asked to contact police on 101 or through Crimestoppers on 0800 555 111.