The 22 humans who live on Aoshima, off Ehime prefecture, are greatly outnumbered by a population of over 120 cats.
Originally brought in to deal with mice infesting fishing boats, the cats now eat scraps, crops or food given to them by tourists or local people.
The big increase in visitors to the island has worried the elderly residents living there because it might disrupt their quiet lives.
Tourists from around Japan have been flocking to a tiny fishing community, to see what has been nicknamed Cat Island.