PROBLEM TO BE SOLVED: To provide a combine harvester suppressing heat radiation of high temperature exhaust gas exhausted from an engine, removing particulate substances in the exhaust gas by a DPF with excellent thermal efficiency and being capable of decontaminating the exhaust gas by disposing the DPF at a position immediately after the engine downstream of a threshing section and a tank inclination bottom wall of a grain tank.SOLUTION: When a DPF 26 for removing particulate substances contained in exhaust gas is disposed inside a space portion 29 formed by a threshing section 6 and a lower side of a tank inclination bottom wall 20 of a grain tank 8 at a position immediately after an engine 11, a cover body 27 is installed on a travel machine base 4 while the DPF 26 is being accommodated in the box-shaped cover body 27 consisting of a rectangular bottom wall 27a as viewed in a plane view, a front wall 31 and a rear wall 32 having inclined sides at upper portions at a front and a rear of the bottom wall 27a and being erected and a right inclined side wall 33 and a left inclined side wall 35 formed so as to individually connect right oblique sides and left oblique sides of the front wall 31 and the rear wall 32, having the right inclined side wall 33 and the left inclined side wall 35 having surfaces connected to each other and being covered.
