Abstract: In an ejector pump provided within a saddle-shaped fuel tank for an automotive vehicle to feed fuel from a subchamber to a main chamber through a suction pipe due to a vacuum generated by fuel returned from an engine to the fuel tank via a return pipe, the ejector pump comprises a return pipe connecting portion connected to the return pipe; a suction pipe connecting portion connected to the suction pipe; a nozzle formed at an end of the return pipe connecting portion; a pump housing coupled to the two pipe connecting portions, for forming a vacuum chamber and a throat portion; and in particular elastic reverse-conical shaped check valve provided within the return pipe connecting portion to prevent fuel from flowing reversely from the fuel tank in case of trouble. Further, since the check valve can be used in common with a sealing member and further with the nozzle, it is possible to simplify the ejector pump structure and assembly work without reducing the fuel tank capacity.