The 2021 Autobacs Super GT Series was a motor racing championship based in Japan for grand touring cars. The series is sanctioned by the Japan Automobile Federation (JAF) and run by the GT Association (GTA). It was the twenty-ninth season of the Japan Automobile Federation Super GT Championship which includes the All Japan Grand Touring Car Championship (JGTC) era, and the seventeenth season under the Super GT name. It was the thirty-ninth overall season of a national JAF sportscar championship, dating back to the All Japan Sports Prototype Championship.
TGR Team au TOM'S and drivers Yuhi Sekiguchi and Sho Tsuboi won the GT500 class championships, driving the Toyota Supra, after overcoming a 16-point deficit in the final round of the season.[1] The titles were secured in controversial circumstances as championship leader Naoki Yamamoto of Team Kunimitsu was taken out from a title-clinching position by GT300 class driver Ren Sato with 15 laps remaining in the final race of the season.[2] Driving the new Subaru BRZ, Takuto Iguchi and Hideki Yamauchi won the GT300 class championships for R&D Sport, giving Subaru their first-ever title in Super GT competition. It was also the first drivers' title for both Iguchi and Yamauchi, and the first for the R&D Sport team.