Police have charged a 21-year-old man following investigations into two armed robberies that occurred in Mackay earlier this month.

It will be alleged around 9.45pm on November 3, a man entered a sandwich shop on Nebo Road and threatened two female employees with a knife before fleeing with a sum of cash from the register.

The employees were not physically injured during the robbery.

It is further alleged around 8.30pm on November 6, a man entered an Ooralea supermarket on the Peak Downs Highway and threatened a female employee before fleeing with a sum of cash from the register.

The 22-year-old woman received minor injuries to her arm from the knife, but did not require medical treatment.

A 21-year-old Townsville man has been charged with three counts of deprivation of liberty, two counts of armed robbery and enter premises with intent to commit indictable offence, and one count of burglary.

He will appear in the Townsville Magistrates Court this afternoon.