FUEL TANK STRUCTURE OF ALL-TERRAIN VEHICLE

A fuel tank structure of an all-terrain vehicle is provided. The all-terrain vehicle includes a vehicle frame unit, a fuel tank arranged on the vehicle frame unit, a seat cushion arranged on the vehicle frame unit, a pair of rear wheels rotatably mounted to a rear section of the vehicle frame unit, and a power unit arranged on the vehicle frame unit. The power unit is connected to an exhaust unit. The vehicle frame unit includes a rear carrier rack and a rear ancillary tube assembly. The fuel tank is arranged rearwardly of the power unit and located below the rear carrier rack. The fuel tank includes a body portion, which is formed with a lower buffering fuel accommodation extension section extending in a direction toward a lower side of the vehicle body, so as to increase the weight of the fuel tank.