A fuel pump and a fuel filter inside a fuel tank and a pressure regulator are supported by a cover closing for an opening of the fuel tank. The fuel sucked by the fuel pump flows into the fuel filter and flows out to the lower side chamber of a filter housing after being filtered by an element. The fuel consumed at the fuel consumption device such as an internal combustion engine is supplied through a fuel passage extending upward from the lower side chamber of the filter housing. On the other hand, water mixed in the fuel is accumulated in the lower side chamber. Especially, glass fibers having high water affinity is mixed in the filter element, so that water is trapped, becomes water drops, and fall to the lower side chamber. Water drops return to the fuel tank with surplus fuel through the pressure regulator disposed at the bottom of the housing.