Yoshio Okamoto (岡本佳男, born 10 January 1941) is a Japanese chemist, who was awarded the 2019 Japan Prize for his groundbreaking work in asymmetric polymerization and its practical applications in drug discovery. Okamoto was the first to prove that synthetic polymer conformations could be controllable, publishing work on asymmetric polymerization from 1979 onwards. This led to the development by Okamoto and others of helical polymers for use in high performance liquid chromatography columns (HPLC), enabling easy separation of chiral drug molecules.