To prevent fuel from flowing out outside a fuel tank by forming a ceiling surface into a circular cone shape rising toward a flow outlet.

A ceiling surface 4A of a housing main body 3A is formed into a circular cone surface which raising toward a flow outlet 5. A lower end of the flow outlet 5 is positioned on an upper side from the ceiling surfaces 4A, and a circumferential groove 8 opened to the lower side is disposed around the flow outlet 5. Since the ceiling surface 4A is formed into a circular cone shape rising toward the flow outlet 5, air is collected to a ceiling top part as a low end part of the flow outlet 5 in the case where a valve element 15 falls down. Accordingly, fuel does not flow into the flow outlet 5, and not flow to the outside of a fuel tank T. Since a valve seat 6 as a lower end of the flow outlet 5 is positioned on the upper side from the ceiling surface 4A, fuel does not flow into the flow outlet 5, and not flow to the outside of the fuel tank T.