The bear entered the grocery store in Numata north of Tokyo on Tuesday.
It came in through the main entrance and stayed for about four minutes, says a store employee.
It almost climbed up onto the fish counter and damaged the glass. In the fruit department, it knocked over a pile of avocados and trampled them.
About 30 to 40 customers were in the store at the time.
On Wednesday, a man has been found dead in the Iwate region after what is believed to be another bear attack, reports public service company NHK.
Wild bears have appeared in residential areas in Japan in recent years. Between April and September, 108 people have been injured by bears in Japan. Five of them have died.
