The present disclosure provides a suction filter that filters a fuel inside a fuel tank of a vehicle. The suction filter includes a filter element, a partitioning wall element, a passage element, and an open/close valve. The filter element is disposed in and exposed inside of the fuel tank. The filter element filters a stored fuel stored in the fuel tank. The partitioning wall element is arranged in the inside space to divide the inside space into a first space and a second space that is lower than the first space. The inlet to take in the filtered fuel is open in the second space. The passage element defines an inflow opening open in the first space, an outflow opening to which a negative suction pressure is applied through the inlet, and a flow passage through which the filtered fuel flows. The open/close valve closes the inflow opening when a liquid level of the filtered fuel is above the partitioning wall element and that closes the inflow opening when the liquid level is below the partitioning wall element.