PROBLEM TO BE SOLVED: To reduce, by lowering the temperature of an outer peripheral surface of an exhaust pipe, the failure of neighboring equipment caused by heat and lower the temperature of exhaust gas to lessen deterioration in the environment of workers.SOLUTION: An exhaust gas cooling device is equipped with an exhaust tube (61) for guiding exhaust gas of an engine (9) to the outside. The exhaust tube (61) is formed of an inner exhaust pipe (61A) and an enclosure tube (61B) enclosing the outer periphery of the exhaust pipe (61A). Between the outer peripheral surface of the exhaust pipe (61A) and the inner peripheral surface of the enclosure tube (61B), a fluid chamber (100) is formed for letting a fluid such as air, water and oil flow spirally along the outer peripheral surface of the exhaust pipe (61A). A fluid supply port (U) is provided at one end of the fluid chamber (100), and a fluid discharge port (D) is provided at the other end of the fluid chamber (100). An injection nozzle (N1) for injecting the fluid in a tangential direction of the outer peripheral surface of the exhaust pipe (61A) is connected to the supply port (U), and a suction nozzle (N2) is connected to the discharge port (D).
