The invention provides a combine harvester capable of easily and efficiently cleaning and overhauling a bearing network. The combine harvester includes a thresher (4) including a threshing portion which throws harvested straws entirely into a threshing chamber and uses free rotation to drive a threshing drum for threshing, and a filtering portion that filters the threshed straws from the threshing chamber via a freely-swinging filtering device. Besides, the combine harvester also includes a pivoting support mechanism (81) which forms an upper transverse sidewall portion (71a) of the threshingchamber of the thresher (4) by supporting in a manner of freely swinging, opening and closing, and a loading/unloading mechanism (80) which supports the upper transverse sidewall portion (71a) in a manner of freely loading and unloading.