PROBLEM TO BE SOLVED: To provide a tilling work machine having improved ground leveling performance. SOLUTION: In a tilling work machine comprising a rotary and a rear cover for leveling a field cultivated by the rotary, a middle part of a ground plate constituting the rear cover is bent, and a ground surface and a soil are applied to the ground plate. A flat surface is formed, and the curved surface that connects the soil push surface and the soil flat surface has a center position of the bending radius lower than the average height of the soil that is pushed up by the soil push surface and has the bending radius. Is larger than 30 mm and smaller than 70 mm, a groove portion is provided on the soil level surface in a direction intersecting at right angles to the traveling direction, and the cross-sectional shape of the groove portion has a field scene at the bottom and a field scene. It has a substantially wedge shape with two oblique surfaces forming an acute angle as hypotenuses. [Selection diagram] Fig. 15【課題】整地性能を向上させた耕耘作業機を提供する。【解決手段】ロータリーと、前記ロータリーによって耕された圃場を均すリヤカバーと、を備える耕耘作業機において、前記リヤカバーを構成する整地板の中途部分が曲げられて当該整地板に土押面と土均面が形成されており、前記土押面と前記土均面をつなぐ曲面は、その曲げ半径の中心位置が前記土押面に押されて盛り上がった土の平均高さよりも低く、前記曲げ半径は、３０ｍｍよりも大きく７０ｍｍよりも小さい値であり、前記土均面には、進行方向に対して直角に交わる方向に溝部が設けられ、前記溝部の断面形状は、圃場面を底辺とし圃場面に対して鋭角となる二つの斜面を斜辺とした略楔形状である。【選択図】図１５
