The JGTC is run by the GT Association, which was founded in 1994 as a successor to the failed Japan Sport Prototype Car Championship (JSPC). The collapse of JSPC motivated various companies and organizations in the automotive and racing industries to establish a series that was more fan-friendly and gave a better return to sponsors.

In researching the failure of the JSPC, the GT Association found an over-reliance on technology that led to an explosion of costs, eventually killing the series. Too much emphasis was placed on obscure cars the public could not identify with, and the entertainment value in the end was minimal. JGTC set out to find an optimal balance between technology, human drama and entertainment. The basis for the series became production cars we could all relate to. Limits were set on power output to prevent costs from spiraling out of control.

The series started modestly with a field of 18 cars that included veteran drivers such as Masahiro Hasemi and Kunimitsu Takahashi (currently the chairman of the GT Association). Race attendance was equally modest. However, within a period of 7 years, the JGTC reached the pinnacle of motor racing in Japan, boasting an impressive field of 48 teams and attracting over 45,000 fans on race day.

JGTC consists of two classes, GT500 (max. 500hp) and GT300 (max. 300hp). Horsepower is controlled through air restrictors.

Cars eligible for GT500: JAF-GT(class 1), Le Mans* cars and cars specially authorized by the JAF**.
Cars eligible for GT300: JAF-GT(class 2), Le Mans cars and cars specially authorized by the JAF.

* Le Mans cars : Cars classified as GT2 before 1998 or GTS and Le Mans GT after 1999. However, those cars need to meet JAF-GT regulations of 2001.
** Cars specially authorized by the JAF: FIA-GT homologated cars, Grand American GT cars, and DTM cars from the year 2000.

Each car is obligated to have 2 drivers. Both drivers need to drive in qualifying and the race to receive championship points. A driver change during the race is mandatory and one driver may not drive more than 2/3 of the total race distance. Drivers needs to hold a valid sporting license of International grade C or above.

Official qualifying is divided into two 60-minute sessions. Each session is divided into three 20-minute segments, one for GT500, one for GT300 and one joint segment. Each driver/car must qualifying within 107% of the average set by the three fastest cars in each class.

The race distance is no less than 250km and no more than 1,000 km. At least one pit stop for a driver change, fuel and tires is mandatory.

The starting procedure begins with an 8-minute warm-up, 45 minutes prior to the start of the race. This is followed by a formation lap and the rolling start. When the pace car leaves the track, and the green light turns on, the race is started. No passing is allowed until the start-finish line is crossed.

Commercial, unleaded, high-octane gasoline (within 102 RONs) is used.

During the race only 5 people can work on a car inside the pit at the same time. Two people to change tires, two to refuel the car and 1 for other tasks. There is no limit to the number of crew members that do not touch the car directly. The car jack may not be used while the car is being refueled, meaning tire changes must occur after the fuel has gone into the car.

JGTC uses a system of handicap weights to ensure a level playing field. Weights are added after a race for the following:

• Finishing first, second or third
• Qualifying first, second or third
• Setting the fastest race lap

The maximum total handicap weight is 120kg for GT500 and 80kg for GT300. If a car running a handicap weight finishes sixth, 10kg is removed from the total in GT500 and 5kg in GT300. Handicapped cars that finish seventh or lower will loose 20kg in GT500 and 15kg in GT300. Handicaps for qualifying and fastest lap cannot be removed. The following is a table showing weight handicaps: