The events took place Friday night in Manosque, in the Alpes-de-Haute-Provence.
The owner of the tobacconist of the Mount of Gold has been robbed by an armed individual who had the face concealed.
But his dog, trained to react to the voice of his master in case of an assault, threw himself on the gunman.
The animal was then disarmed the assailant. The latter had then preferred to take the flight.