Hiroya Okuyama (奥山 広也 Okuyama Hiroya) is a member of Team Spiral, and is known within the team as Zero One (スパイラルの「01ゼロワン」Supairaru no "01 zero wan"').
Okuyama too believes in Ryuji Ikeda's "Zero Theory" and is disappointed when he won't be able to use his car's full potential due to the rain.
Okuyama, unlike Ikeda, is very arrogant and confident in his abilities. He also refuses to greet Project D upon meeting them.
His battle against Takumi Fujiwara is raced in the team's first fog battle, but the result was similar to Takumi's battle against Nobuhiko Akiyama of the Saitama Alliance: Takumi used half his potential until the first hairpin, where he left Okuyama behind.
Hiroya Okuyama also appears in MF Ghost as a recurring character, runs a tuning shop called "Spiral Zero Auto Shop" and helps the protagonist Kanata tune his GT86. He also became a nicer person, indicating that his defeat by Takumi may have changed his personality.