Hioki is a city in Kagoshima Prefecture, Japan. It is located in the southern part of the prefecture, on the island of Kyushu.
As of 1 July 2024, the city had an estimated population of 45,720 in 22,560 households, with a population density of 180 persons per square kilometre. Its total area is 253.01 square kilometres (97.69 square miles).