Hattori began competing in Japanese Formula Three in 1988, taking time to develop through the field before winning the championship in 1990 driving for Kawai Steel Le Garage Cox Racing with a Mugen engine. He took four race victories and secured the title at the top of the standings, establishing himself as one of Japan's quickest single-seater drivers.
Armed with the Japanese F3 title, Hattori secured a late-season drive with Coloni in 1991, replacing Pedro Chaves in the Formula One World Championship. The Coloni C4 was underpowered and uncompetitive, and Hattori failed to pre-qualify for both the Japanese Grand Prix and the Australian Grand Prix that year. The outcome was a reflection of the Coloni machinery's limitations rather than his ability, but the Formula One opportunity went no further.
Despite the F1 disappointment, 1991 produced one of the landmark results of Hattori's career. Driving a Nissan Skyline R32 GT-R for Team Zexel alongside David Brabham and Anders Olofsson, he won the Spa 24 Hours outright — a prestigious endurance victory at one of motorsport's most demanding circuits.
Hattori became a consistent podium finisher in the Japanese Touring Car Championship throughout the 1990s. He won the 1993 title driving a Mooncraft Honda Civic. He reclaimed the championship in 1996 driving a Mooncraft Honda Accord, collecting five wins and three second-place finishes from 12 starts across the season. He also participated in the 1995 Le Mans 24 Hours with a Honda NSX but was not classified.
Hattori competed in the Japan Grand Touring Car Championship from its early years. In 1996 he drove a McLaren F1 GTR for Team Lark and won three races in the GT500 class, finishing second in the GT500 standings. He subsequently raced in the JGTC and its successor Super GT across multiple subsequent seasons in various machinery including Nissan Skyline GT-R, Honda NSX and Toyota Supra variants.
In the mid-to-late 1990s Hattori spent time in American open-wheel competition. He raced in Indy Lights from 1997 to 1998 for Team Green, finishing sixteenth in 1997 and tenth in 1998. He made a brief appearance in the CART World Series in 1999 for Walker Racing, with a best finish of fourteenth. In 1997 he also served as a test driver for Dome's F1 development programme, evaluating the Dome F105 prototype at Suzuka.
Hattori returned to Japan's top domestic formula and was a persistent frontrunner. He finished runner-up in the Formula Nippon championship in 2001, recording three wins across the season — one position short of the title.
Hattori continued racing in Super Taikyu and related Japanese domestic series well into the 2020s, still competing in Super Taikyu events in 2025 and 2026. He is also widely known as a presenter on Best Motoring, Japan's long-running automotive testing video series. He is unrelated to fellow Japanese racing driver Shigeaki Hattori.