Detective Sergeant David Cameron said: “ It was reported that a man wearing a black coat with a hood and a balaclava and armed with a suspected firearm entered the service station at around 10pm and demanded money.
“A sum of money was handed over and the man left the scene on foot in the direction of the Braniel estate. There were no reports of any injuries.
“I would appeal to anyone who has any information which may assist us with our enquiries to contact CID in Castlereagh on 101. Information can also be passed anonymously through Crimestoppers on 0800 555 111.”
There has been a spate of robberies across east Belfast in recent months.
Those targeted include petrol stations, conevenice stores, bars/restaruants and off-licences.