It happened around 4 p.m. Saturday near Algonquin Street and Davenport Drive.
Police say two armed men smashed their way into the business and tried holding up the owner.
The owner, however, was also armed and shot at the suspects in self-defense, police said.
The would-be thieves managed to escape unharmed and fled the scene.
Police said a customer who was inside the store at the time was cut by broken glass, but no other injuries were reported.
A detailed description of the suspects wasn't immediately released.
The incident remains under investigation.