Nobuto Hosaka is a Japanese politician and the current mayor of Setagaya in Tokyo. In addition, he was a member of the House of Representatives for the Social Democratic Party until July 21, 2009.

Setagaya is a special ward in the Tokyo Metropolis in Japan. It is also the name of a neighborhood and administrative district within the ward. Its official bird is the azure-winged magpie, its flower is the fringed orchid, and its tree is the Zelkova serrata.