Abstract: A vehicle fuel tank in which the tank bottom has a protrusion so as to provide a space for accommodating the frame and other parts of the vehicle under the fuel tank, the protrusion defining a plurality of compartments in the fuel tank. An overhanging siphon having an opening in the top thereof provides communication between compartments. A fuel inlet pipe and a fuel suction pipe are communicated with a first compartment so that the supply of fuel into the fuel tank and the suction of fuel from the fuel tank are conducted through the first compartment. A valve such as a float valve is provided on the siphon opening.