The PSNI say that at around 9.30 am a man armed with a knife entered the premises on the Falls Road.
Brandishing the knife, he threatened the two staff members before attacking them.
One member of staff, a man in his 50s, was stabbed in the chest and the second, a man aged in his 40s, sustained a stab wound to his arm.
Both have been taken to the nearby Royal Victoria Hospital for treatment but their injuries are not believed to be life threatening.
A 26-year-old man was arrested at the scene for attempted murder and attempted robbery.
He is currently being quizzed at the PACE custody suite in Musgrave PSNI station.
Detective Sergeant Michael Hawthorne is appealing for witnesses to contact him on the 101 number.
Or, information can also be passed anonymously to Crimestoppers on freephone 0800 555 111.