A fuel filter having a filter element and fuel pump in a housing is disposed in a fuel tank. The filter element has a partition in contact with the fuel outlet side of the element. Fuel filtered by the element is divided into two stream passages, one of which is a return passage to the fuel tank and the other is a supply passage to fuel injectors of a common rail mounted on an engine. The amount of the stream returning to the tank is larger than the amount of the other stream so that a substantial amount of foreign particles in the fuel tank are carried by the returning stream and filtered. As a result, foreign particles may not so thickly accumulate on the filter portion in the supply passage.