Yamaguchi (山口市, Yamaguchi-shi, literally "the entrance to the mountain") is the capital city of Yamaguchi Prefecture, Japan. The city was founded on April 10, 1929. As of February 1, 2010, the city had an estimated population of 198,971 and a population density of 194.44 persons per km². The total area is 1,023.31 km².
Yamaguchi is home to the Buddhist temple, Rurikō-ji (瑠璃光寺, Rurikō-ji), with its five-story pagoda.
Yamaguchi is served by Yamaguchi Ube Airport in nearby Ube.