Abstract: In view of the problems of high cleaning loss rate and high impurity content of pod in the cleaning process of half feeding peanut combined harvester at present, a secondary cleaning device was designed based on the damage mechanism of peanut fruit after primary cleaning, which mainly included conveying chain, bar screen, screen frame, hydraulic cylinder and sliding plate, and the basic parameters of the device were determined. Through the analysis of ADAMS software, the collision model between peanut and the device in the cleaning process was established, and the screen speed, screen installation height and screen inclination angle were determined as the main influencing factors. The peanut variety “Yuhua 14” was tested and studied. The results show that the screen installation height is 29 cm, the screen rotation speed is 147 r/min, and the screen installation angle is 19°. The corresponding peanut fruit impurity content is 1.65%, and the cleaning loss rate is 1.37%. Through the analysis, the operation effect of the peanut combined machine with two-row and four-row with this device has been significantly improved.