To provide a combine harvester which can efficiently separate and filter foreign matters such as waste straw in second crops in a grain-lifting cylinder for returning second crops to a thresher.SOLUTION: A first grain-lifting cylinder (36) for conveying grains from a thresher (4) to a grain tank (7) is provided, and a second grain-lifting cylinder (41) for returning second crops from the lower part to the upper part of the thresher (4) by connecting the rear part and the front part of a right wall (4B) of the thresher (4) is provided in a rear lower inclined posture at the left side of the first grain-lifting cylinder (36). A conveying spiral (46) and a cylindrical body (45) covering the conveying spiral (46) are provided in the second grain-lifting cylinder (41), and a discharged dust filtering member (42A) having a plurality of filter holes is provided in a dust discharging port (42) formed at the lower surface side of the second grain-lifting cylinder (41). The filter holes of the discharged dust filtering member (42A) are formed in a slender shape along the outer peripheral edge of the conveying spiral (46).SELECTED DRAWING: Figure 14【課題】脱穀装置に２番物を還元する揚穀筒において、２番物中の藁屑等の來雑物を効率的に分離、濾過することができるコンバインを提供する。【解決手段】脱穀装置（４）からグレンタンク（７）へ穀粒を搬送する第１揚穀筒（３６）を設け、第１揚穀筒（３６）の左側に、脱穀装置（４）の右壁（４Ｂ）の後部と前部を連結して脱穀装置（４）の下部から上部へ２番物を還元する第２揚穀筒（４１）を後下がり傾斜した姿勢で設け、第２揚穀筒（４１）に、搬送螺旋（４６）と、この搬送螺旋（４６）を覆う筒体（４５）を設け、第２揚穀筒（４１）の下面側に形成される排塵口（４２）に、複数の濾過孔を有する排塵濾過部材（４２Ａ）を設け、排塵濾過部材（４２Ａ）の濾過孔を搬送螺旋（４６）の外周縁に沿って細長の形状に形成した。【選択図】図１４
