Gattsu Jōnai

is a Japanese racing driver and businessman.

Racing career Jyonai started karting in 1988; he is noted for his extensive experience in kart racing, having won numerous karting championships. He moved to car racing in 1993, racing in the Suzuka 1000 km in the Proto 2 class; he won on his debut. his best finish in the championship is fifth, achieved in his first year in the series. Outside of racing, Jyonai is the CEO and President of Marusho Co. Ltd., a company involved in the lighting, security and construction sectors. He is also a lecturer at the karting classes of Honda Racing School Suzuka as well as a color commentator for various television programs.

Jyonai occasionally competes using the pseudonym ; Jyonai says he took the name from comedian Guts Ishimatsu. In more recent years, he has reverted to using his real name.

Racing record Complete Super GT results (key) (Races in bold indicate pole position) (Races in italics indicate fastest lap) Season still in progress.