Yanai () is a surname of Hebrew origin. Notable people with this surname include:
Hagar Yanai (born 1972), Israeli writer Itai Yanai (born 1975), Israeli-American biologist Michal Yannai (born 1972), Israeli film actress Moshe Yanai (born 1949), Israeli electrical engineer Shmuel Yanai (1921–2011), Israeli naval commander Zvi Yanai (1935–2013), Israeli writer