To propose a structure for further improving an aspirating force in an aspirator for recovering fuel.

This aspirator 30 for recovering fuel has a structure for aspirating residual fuel in an engine fuel passage through an aspiration passage 34 communicated with a drive passage 31 by flowing fuel in the drive passage 31, in which a bottle neck is formed, to generate a negative pressure. Heat-insulation layers 35, 36 are formed around the drive passage 31. By the heat-insulation layers, it becomes difficult to transmit an outside temperature to the drive passage. Meanwhile, it becomes difficult to release temperature fall due to vaporization of the fuel in the drive passage to outside, so that the temperature of the drive passage can be restrained and the vaporization of the fuel flowing as drive fluid can be restrained than conventional, so as to improve an aspirating force.