Ryōtarō Sugi (杉良太郎, Sugi Ryōtarō, real name 山田勝啓 Katsuhiro Yamada) (born 14 August 1944, Kobe) is a Japanese singer and actor. He is the father of actor Jundai Yamada.

He appeared in Sukima Kaze, which sold over a million copies. His acting credits include 18 films. On television, he specialized in jidaigeki roles, appearing as the first Suke-san in Mito Kōmon (seasons 1 and 2); his son Jundai Yamada played Kaku-san in the same show (seasons 29 to 31). He played the lead character in Ōedo Sōsamō, appearing from 1970-74. In the 1971–72 season he portrayed Isshin Tasuke in a series of the same name, and from 1975 to 1977 he played Tōyama no Kin-san; his Sukima Kaze was the theme song. With former Miss Universe contestant Hisako Manda he starred in Kenka-ya Ukon (1992–94).