A construction machine includes: a lower propelling body; and an upper slewing body which is slewably mounted on the lower propelling body. The upper slewing body includes: an engine room provided with an intake opening for introducing cooling air from an outside and a discharge opening for discharging cooled air to the outside; a duct provided in the engine room so as to communicate with the discharge opening and adapted to discharge the cooled air to the outside of the engine room from the discharge opening; and an exhaust gas pipe which guides exhaust gas discharged from the engine into the duct. The discharge opening and an outlet of the duct are open downward from the engine room. A portion on a distal end side of the exhaust gas pipe is inserted into the duct. The duct and the exhaust gas pipe are configured to cause the exhaust gas to be mixed with the cooled air in the duct and cause the mixture of the exhaust gas and the cooled air to be discharged downward from the discharge opening.