EVAPORATED FUEL PROCESSING DEVICE

An evaporated fuel processing device is configured to collect evaporated fuel from a fuel tank of an internal combustion engine. The evaporated fuel processing device includes the fuel tank, a canister, a tank sealing valve, a switching valve, and a differential pressure sensor. The fuel tank stores fuel for the internal combustion engine. The canister adsorbs evaporated fuel generated in the fuel tank. The switching valve switches between allowing and blocking off communication between the canister and open air. The differential pressure sensor detects a system differential pressure between the pressure on the canister side of the tank sealing valve and the pressure on the fuel tank side of the tank sealing valve in the detection target system.