CONSTRUCTION MACHINE

An exhaust gas aftertreatment device (30) provided to an upper portion of an engine (7) includes a right and left pair of first and second aftertreatment units (31, 32), into which exhaust gas from the engine (7) dividedly flows, each including a first exhaust gas emission control system (33) on an upstream side, a second exhaust gas emission control system (34) on a downstream side and a communication pipe (35) through which the first and second systems (31, 34) are in communication with each other, the first and second systems (33, 34), while being arranged side by side in a right-and-left direction, being oriented so that a flow direction of the exhaust gas flowing therein is parallel with a front-and-rear direction. When the device (30) is seen in the front-and-rear direction, an outer linear envelope (E) tangent to the first system (33) and the communication pipe (35) of each of the units (31, 32) extends upward while tilting toward a right-and-left center of the engine (7).