Demachi (written: 出町) is a surname. Notable people with the surname include:
*
Giuseppe Demachi
Giuseppe Demachi (9 June 1732 – 1791 or after) was a composer born in Alessandria, Italy. He served as a leading violinist in the city of his birth and later in the city of Geneva with the Concerto di Ginevra of the Societé de Musique. He ...
Italian composer
*, Japanese speed skater
*, Japanese Olympic athlete
{{Surname
Japanese-language surnames