A combine in which drive of normal and reverse rotation of a harvesting section (10) is made by a cost effective and simple structure. A power transmission case (36) is provided forward, relative to a travel machine body, of a threshing device (5) of the combine. In the power transmission case (36) are arranged a case input shaft (37) to which drive force from an engine (20) is transmitted, a threshing drum output shaft (38) installed in the front-rear direction relative to the travel machine body and operatively associated with the case input shaft via a bevel gear mechanism (43) So as to transmit drive force of the case input shaft to a threshing drum (Sa), and a harvesting output shaft (39) operatively associated with the case input shaft via the bevel gear mechanism so as to be driven in the opposite direction to the direction of rotation of the case input shaft, The combine has a normal rotation clutch (40) for transmitting drive force in the direction of normal rotation to the harvesting input shaft (42) of the harvesting section and also has a reverse rotation clutch (41) for transmitting drive force in the direction of reverse rotation to the harvesting input shaft.