Yokoi Yayū (横井 也有, October 24, 1702 – July 15, 1783) was a Japanese samurai best known for his haibun, a scholar of Kokugaku, and haikai poet. He was born Yokoi Tokitsura (横井 時般), and took the pseudonym Tatsunojō. His family are believed to be descendants of Hōjō Tokiyuki.