Ryōtarō or Ryotaro is a masculine Japanese given name which can refer to:
Ryotaro Azuma (1893–1983), Japanese physician and bureaucrat, Governor of Tokyo 1959 to 1967Ryōtarō Okiayu (born 1969), Japanese voice actorRyōtarō Shiba (1923–1996), Japanese authorRyōtarō Sugi (born 1944), Japanese singer and actorRyotaro Tanose (born 1943), Japanese politician of the Liberal Democratic PartyRyotaro Nogami, a character from Kamen Rider Den-O