Detectives have charged a 28-year-old man following an investigation into seven armed robberies in the South Brisbane District between August and January.

On August 28 a man allegedly threatened workers with a firearm at a convenience store on Gapap Street in Tarragindi before stealing cash.

It will be alleged on September 17 a convenience store on Shillington Road at Wishart was held up by a man armed with a firearm.

On October 11 a man allegedly produced a firearm and threatened staff at a bottle shop on Newnham Road at Upper Mount Gravatt.

A man allegedly stole a sum of cash after threatening employees with a firearm at a Salisbury liquor store on Toohey Road on November 9.

It will be alleged on December 14 a man produced a firearm before stealing cash at a bottle shop on Wecker Road at Mansfield.

On December 22 a man allegedly threatened staff at a liquor store on Toohey Road at Salisbury before fleeing with cash.

It will further be alleged a man produced a firearm and robbed a convenience store on Mount Gravatt-Capalaba Road at Wishart on January 11.

No one was physically injured in any of the incidents.

A 28-year-old Tarragindi man has been charged with a total of 20 offences including seven counts of armed robbery; ten counts of deprivation of liberty; and one count each of unlawful possession of a weapon, shortening a firearm and possessing a thing.

He will appear in the Brisbane Magistrates Court tomorrow.