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Aiming at the problems that insufficient contact between ground and pickup attachment of spring-tooth topsoil residual plastic film collector, additional releasing film part and rearranged film-retrieving spring teeth was used to improve the structure of residual plastic film pickup attachment. The conditions for residual plastic film to move on the film-releasing rod teeth were analyzed to determine the scope and arrangement of penetrating angle of film-releasing rod teeth. The film-retrieving spring teeth were kinematically and kinetically analyzed to determine the kinematic equation and motion trail of spring teeth in the process of picking up residual plastic film. According to the design principle of Box-Benhnken experiment, taking the forward speed, penetrating angle of film-releasing rod teeth and rotational speed film-delivering chain harrow as experimental factors and the recovery rate and impurities rate of residual plastic film as response values, based on regression analysis and response surface analysis, a mathematical model between forward speed, penetrating angle of film-releasing rod teeth, rotational speed film-delivering chain harrow and recovery rate and impurities rate of residual plastic film was built and the aforesaid factors and their interactions were analyzed. The result showed that the factors that most affected the recovery rate of residual plastic film were the penetrating angle of film-releasing rod teeth, forward speed and rotational speed film-delivering chain harrow in descending order;and the factors that most affected the impurities rate of residual plastic film were the rotational speed film-delivering chain harrow, penetrating angle of film-releasing rod teeth and forward speed in descending order. Design-Expert software was used to obtain the optimal solution to the regression equation, which showed that when the forward speed, penetrating angle of film-releasing rod teeth and rotational speed film-delivering chain harrow were 5.21km/h, 30.8°and 236r/min, respectively, the theoretical maximum recovery rate of residual plastic film and minimum impurities rate of residual plastic film were 91.4% and 3.21%. respectively. Field validation test showed that the recovery rate and impurities rate of residual plastic film under the above parameters were 91.2% and 3.1%, respectively, the error between theoretical and experimental values was less than 3%.