Abstract: To meet the needs of green rice production, a spring-tooth weeding installation which works between seeding lines in paddy field was designed, and the main structure and critical components were designed, and work principle was analysed. Test was carried out in the mechanical planting ground, the line spacing for seedlings was 30 cm, and the spaced in the rows was 14-16 cm. This paper used the 7th day test to discuss, under the help of Design-Expert software to analyze the experiment data, and the interaction effects of cutter rotation speed, forward velocity of the machine, weeding depth on weeding ratio and seeding injury ratio were attained. The primary and secondary factors of effecting weeding quality and the significance of each factors was obtained. Finally, The results showed that the optimum parameters in the 7th day test were: the cutter rotation speed was 186 r/min, the forward velocity was 0.47 m/s, the weeding depth was 37 mm, weeding rate was 75%, and miller injury rate was 3.9%. The results provides a reliable basis for the machine design .