Miyakonojō is a city in Miyazaki Prefecture, Japan. As of 1 November 2023, the city had an estimated population of 158,235 in 72394 hous…Miyakonojō is a city in Miyazaki Prefecture, Japan. As of 1 November 2023, the city had an estimated population of 158,235 in 72394 households, and a population density of 240 persons per km². The total area of the city is 653.36 km², making it the largest city in the prefecture in terms of area.