The incident happened at 10.55pm on Monday, January 28 at the Co-op store in Roxburgh Street when a man entered the premises and allegedly brandished a knife at a member of staff.
Three bottles of whisky and cigarettes were stolen.
A 36-year-old man was arrested yesterday, and is due to appear from custody at Jedburgh Sheriff Court today.
Detective Sergeant Callum Peoples from Galashiels CID said: “We recognised the impact this robbery had on the local community within Kelso and a thorough investigation was conducted, culminating in this arrest.
“Crimes of this nature will not be tolerated and whenever they occur we will utilise all resources at our disposal to bring those responsible to justice.”