To effectively prevent a risk of burn injury in the case that a hand or etc. touches the surface of an exhaust pipe in error.

This exhaust sound-muffling device for an engine 13 includes a muffler 18 provided in an exhaust system for the engine 13 installed in an engine room 11, and the exhaust pipe 19 connected to the downstream side of the muffler 18. The exhaust pipe 19 is formed into a double pipe structure consisting of an inner pipe 20 and an outer pipe 21. A space 22 is provided between the inner pipe 20 and the outer pipe 21 in communication with atmospheric air. The space 22 has an air inlet 23 for outside air to continuously flow thereinto. The outside air flowing into the space 22 suppresses the rise of the surface temperature of the outer pipe 21. The outside air flowing into the space 22 is cool air which is introduced by a cooling fan 16 and used for cooling the engine 13.