Okamoto joined Capcom in 1984 and directed 1942 (1984); SonSon (1984); Gun.Smoke (1985) and Side Arms (1986) in succession in his first two years. His final directoral credit was Forgotten Worlds (1988), an arcade game for Capcom's new CP System arcade board. After this Okamoto became a producer for the company. Two of his notable early producing credits are the beat 'em up title, Final Fight (1989) and Street Fighter II (1991), both of which used character art by Akira Yasuda, who Okamoto recruited for the company.
It was Okamoto's idea that the early-build of Resident Evil 2 ("Biohazard 1.5") was too conclusive in its plot, and that it should be altered to allow further exploration into the fictional universe.