Koga, Fukuoka

 is a city located in Fukuoka Prefecture, Japan. It is northeast of Fukuoka City. The city was founded on October 1, 1997.
As of 2016, the city has an estimated population of 58,094 and a population density of about 1,400 persons per km². The total area is 42.11 km².
Koga Station is on the Kagoshima main line.