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As people pay more and more attention to food safety issues, chemical weeding is increasingly limited. Compared with chemical weeding and artificial weeding, mechanical weeding has the advantage of less pollution and high efficiency, which conforms to the trend of sustainable agricultural development. However, the traditional cultivation can only remove interstage weeds and cannot remove weeds between plants. In order to meet the requirements of mechanical intra-row weeding for maize in China, a cam rocker swing intra-row weeding device was designed. The overall structure and working principle of the weeding device were illustrated and analyzed. The key components of weeding device were designed, such as the cam rocker mechanism and the weeding knife. The factors that affected the effect of weeding were got based on the kinematic and force analysis of weeding device. For the performance of weeding device, the forward speed, spring stiffness coefficient and weeding knife rotating speed were taken as experimental factors, and weeding rate and injury rate were taken as test indexes. The orthogonal test L9 (34) was conducted in the indoor soil bin for getting test factors affect the performance of weeding device work. Test results showed that the order of the various affecting factors were the spring stiffness coefficient, forward speed and weeding knife rotating speed;the best combination was as follows: the spring stiffness coefficient was 60 N/mm, forward speed was 0.6m/s, weeding knife rotating speed was 130r/min. To the optimal level combination of verification experiment: weeding rate was 89.8%, and injury rate was 2.1%.