Dome Co. Ltd (株式会社童夢, Kabushiki Gaisha Dōmu), literally "child's dream", is a Japanese racing car constructor involved mainly in open-wheel and sports car racing.

In 1965, Minoru Hayashi built his first racing car, a rebodied Honda S600 coupe. Belonging to Tojiro Ukiya, it was called the "Karasu" (crow in Japanese), due to its shape. Built on a small budget and in a short time, the Karasu emphasized weight reduction and aerodynamics using FRP materials. The car went on to win its debut race at the Suzuka Clubman Race, despite Hayashi having no experience in racecar construction. In 1966 he went on to build the "Macransa", a more extensively modified Honda S800, to compete at the Japanese Grand Prix. This was followed by the "Kusabi" three years later, which was a Formula Junior racing car, and the "Panic" in 1971.

In 1975 at Takaragaike, Kyoto, Hayashi formed Dome with the intention to manufacture cars with small production runs, using racing machines to develop the technology. Three years after the company's formation in 1978, the company produced its first concept car designed for road use, the Nissan L28-powered Dome Zero (童夢-零, Dōmu Zero), designed to be world’s lowest-riding sports car, with its height set at 980 mm (38.6 in). The Zero made its public debut at the Geneva Motor Show the same year. For the following year, Dome produced a production version of the Zero called the Zero P2, which was exhibited at the Chicago Auto Show and Los Angeles Auto Expo. The car was refused type approval by the Japanese government, however, and was unable to go into production.

Dome entered the 1980s as a sportscar constructor designing and building the Group C spec Toyota TOM'S cars to compete in the All Japan Super Silhouette Championship, and later the All Japan Sports Prototype Championship, and World Sportscar Championship until the end of the 1980s. Dome's vehicles included the Celica C and prototypes from the 83C through to the 88C.

Minoru Hayashi would also assist his cousin Masakazu Hayashi (of the Hayashi aluminum wheel company) establish his own formula car manufacturing concern. After producing cars for Japan's Formula Junior 1600 category for 10 years, their first Formula 3 car was the Hayashi 803 Formula Three car, designed by the two cousins. It was followed by the Hayashi 320 in 1981 designed by Masao Ono, who had also designed the 1976 Kojima F1 car. Osamu Nakako won the All-Japan Formula Three Championship title driving a Hayashi 320. A 320 was also modified for the Formula Atlantic category and won the Macau Grand Prix driven by American Bob Earl. A further development, the 321, saw action briefly in Japan and England. Ono then switched to Dome to work on the sportscar designs, and Hayashi Racing switched to Ralt chassis to win the Japanese F3 title with Kengo Nakamoto.

In 1984, the follow-up Hayashi 322 was a success and helped Shuji Hyodo to win that year's Japanese F3 championship. In 1985, the Hayashi 330 won a single Japanese F3 race, but finishes were good enough to place driver Shuji Hyodo third in season-end standing. A development of the 322, the 331, appeared in a handful of Japanese F3 races in 1986 without success and disappeared quietly. A downturn in the aluminum wheel business is credited in causing Hayashi to abandon racing.

In 1988, Dome would return to production car design, establishing a design studio called Jiotto Design to design cars with its own quarter-scale wind tunnel. The studio produced the Jiotto Caspita supercar, which never went into production due to the recession.

Dome continued to compete with Jan Lammers, Keiji Matsumoto, Ross Cheever and Thomas Danielsson, driving until 1992, when Marco Apicella was signed to drive the new Dome-Mugen F103, taking the title in 1994. The Formula 3000 program continued until 1998 with Shinji Nakano, Katsumi Yamamoto and Juichi Wakisaka but without much success.