A fuel tank used for a general-purpose engine comprises a hollow tank body for storing fuel and a filter disposed within the tank body. The tank body has a bottom with a trap having an internal surface portion lying in a first plane. The filter comprises a tubular body extending from the internal surface portion of the trap and a fluororesin element supported by the tubular body so that a main surface of the fluororesin element lies in a second plane disposed at an angle of inclination relative to the first plane. The fluororesin element has a property of not allowing water to pass therethrough but allowing fuel to pass therethrough.