Kasaoka

 is a city located in Okayama Prefecture, Japan. The city was founded on April 1, 1952. The municipal district also includes 31 outlying islands including seven inhabited islands in the Kasaoka Islands group. 
As of February 28, 2017, the city has an estimated population of 50,160, with 22,446 households and a population density of 370 persons per km². The total area is 136.03 km².
Crime and safety.
The Asano-gumi yakuza syndicate is based in Kasaoka. The Asano-gumi is the only designated yakuza group based in Okayama Prefecture.
Sister cities.
Kasaoka is twinned with: