Yachi is a surname. Notable people with the surname include:
Kento Yachi (born 1988), Japanese baseball player Shotaro Yachi (born 1944), Japanese diplomat Yusuke Yachi (born 1980), Japanese race walker
Fictional Hitoka Yachi, the second manager of the Karasuno High School Volleyball Club in Haikyu!! Madoka Yachi, a mother of Hitoka Yachi in Haikyū!!