Provided is a saddle type fuel tank in which liquid fuel does not reach a canister through an exhaust passage immediately after full-tank refueling. The saddle type fuel tank includes a saddle type tank body and a full-tank regulating valve. The full-tank regulating valve includes a valve body, a float valve, a first hanging pipe communicatively connected to the valve body and having a first opening at a hanging end thereof, and a second hanging pipe communicatively connected to the valve body and having a second opening at a hanging end thereof. The first opening of the first hanging pipe is located at a height corresponding to a full-tank liquid level RA1_full in the first chamber. The second opening of the second hanging pipe is located at a height lower than that corresponding to a full-tank liquid level RA2_full in the second chamber.