Abstract: Since an aspirator 7 is disposed at a position lower than a fuel gallery 11 and an overflow fuel pipe 81, DME fuel remaining in the fuel gallery 11 and the overflow fuel pipe 81 can be more efficiently retrieved to a fuel tank 4 by a combined force of gravity and suction force produced in a suction port 7c of the aspirator 7. Since the vapor-phase pressure delivery pipe opening/closing solenoid valve 74 is disposed at a position higher than the fuel gallery 11, DME fuel in a liquid state remaining in the fuel gallery 11 and the overflow fuel pipe 81 is forcedly delivered under pressure to the suction port 7c of the aspirator 7 by a combined force of gravity and the pressure of a vapor phase 4b in the fuel tank 4. Accordingly, time taken to retrieve the DME fuel in an injection system to the fuel tank after the stop of a diesel engine.