The arrest followed the incident on July 30, where two offenders entered the Dee St Night 'n Day store, one reportedly with a firearm, about 9.30pm.
A member of the public who went to intervene was stabbed by one of the offenders.
Detective Matt Wyatt said the 31-year-old man has been jointly charged with aggravated robbery, wounding with intent to cause grievous bodily harm and two thefts.
He was due to appear in Invercargill District Court this afternoon.
The other offender, a 38-year-old man, was arrested and charged on Wednesday.
He appeared in Invercargill District on the same day and is due to reappear on September 1.
Police confirmed today the victim of the stabbing has now been released from hospital and is recovering at home.
Enquiries were ongoing in regards to identifying a third person who is believed to have assisted with the aggravated robbery.
Police thanked the Invercargill community for their assistance in the inquiry.
