PROBLEM TO BE SOLVED: To solve such a problem that an exhaust air cleaning apparatus, DPF, is not properly restored when temperature decreases, so that exhaust resistance increases and engine output decreases.SOLUTION: In a combine harvester, an engine compartment 19 of an engine 11 is formed in front of a grain tank 5, and an exhaust gas cleaning apparatus 15 which has DOC 16 burning unburnt gas in the exhaust air from the engine 11 and DPF 17 collecting particulate matter in the exhaust gas, is installed in an exhaust pipe 14 connected with the engine 11 which drives a travelling device 2, a thresher 3, and a reaping part 4. The exhaust gas cleaning apparatus 15 is placed in a space 18 behind the engine 11 between the grain tank 5 and the thresher 3. The exhaust gas cleaning apparatus 15 is surrounded by a cover 27. The exhaust gas cleaning apparatus 15 is provided with a sensing part 29 and a sensor 28 which has a sensing signal processing part 30. The sensing signal processing part 30 of the sensor 28 is arranged outside the cover 27.
