To secure safety against a fuel leak when a vehicle is turned over regardless of the posture of the vehicle.

This fuel tank 1 is linked to a canister 2 which is placed at one side of a front of a vehicle body through a cut-off valve 4 and evaporation line 3 disposed on the wall of the ceiling of the fuel tank 1. In this case, the cut-off valve 4 is placed offset so that it is located above the fluid level at a specified fuel amount for the fuel tank 1 when the vehicle is turned over to the side where the canister 2 is located. In addition, at the top of the fuel tank 1, an expandingly protruding portion 7 which protrudes to the side opposite to one where the canister 2 is located is provided.