It happened at the 3 and 1 Variety Store on the 6700 block of Castor Avenue just before 4:00 p.m.
Police say 5 men wearing masks, beat and stabbed the 66-year-old victim.
He was rushed to Aria Torresdale Hospital where he is listed in guarded condition.
The incident remains under investigation.
Anyone with information is asked to contact Philadelphia Police.