PURPOSE: To provide a fuel tank which may be easily formed and fabricated at a low cost while having a high strength and a high quality in sealing, by incorporating an air breed pipe connected at its lower end with a tank body and at its upper end with a fuel filler pipe, integrally with the filler pipe.

CONSTITUTION: A fuel filler pipe 2 is connected at its one end to one side of a tank body 1 of a fuel tank T, and at its the end to a fuel supply section. An air- breed pipe 3 is connected at its lower end with the tank body 1 and at its upper end with the fuel filler pipe 2. The tank body 1, the fuel filler pipe 2 and the air-breed pipe 3 are integrally incorporated with each other by blow-molding. Therefore, the facility of fabrication of the tank is satisfactory, and no coupling is required. Accordingly, the tank may have a perfect sealability and is stable its strength so that the practical use and reliability of the tank is sufficient.