Takeharu Yamanaka

is a Japanese politician and current mayor of Yokohama, the capital of Kanagawa Prefecture. He defeated incumbent mayor Fumiko Hayashi in the 2021 Yokohama mayoral election. His independent campaign was supported by the Constitutional Democratic Party, Social Democratic Party, and the Communist Party of Japan. Yamanaka's campaign focused on the opposition for a planned integrated resort development and casino for the city which was to be built on Yamashita Pier, criticism against the government's response to the COVID-19 pandemic, and additional sister city relationship with San Francisco, California.

Yamanaka formerly worked as a professor at Yokohama City University and as a data scientist.

On 16 January 2026, Yamanaka issued a public apology after Yokohama's human resource chief, Jun Kubota, accused Yamanaka of using terms such as "idiot" and "human scum" to disparage staff. In July 2026, a third-party investigation confirmed these allegations and also Yamanaka saying things like "everyone over 55 is stubborn and useless", even telling a official to "disembowel" if he failed to secure a bid to host an international conference. On 28 August 2026, two weeks after some of Japan's major political parties urged him to step down from his post, Yamanaka announced his intention to resign as the mayor of Yokohama.