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In order to improve the performance of airsuction seeder with corn roller, the structure of airsuction disc of airsuction seeder was improved by using elastic rubber according to the characteristics of corn film planting in northwest arid areas. Three factors affecting seed suction ability were obtained by force analysis of suction process of suction cup, which were the rotation rate of suction cup, negative pressure of suction chamber and suction hole diameter of suction pad of seed metering cup. To obtain better performance parameters of elastic suctionnozzle type corn roller seeder, on the selfmade experimental platform of elastic suctionnozzle type corn roller seeder, and according to the central composite design experimental design principle of response surface methodology, the rotation rate of suction tray, negative pressure of suction chamber, suction hole diameter of suction pad of seeder were taken as factors, and the qualified rate of plant spacing was main target, taking into account the reseeding. The response values of seeding rate and seeding failure rate were obtained. The results of bench experiment were fitted by multivariate regression and variance analysis. The two regression models of plant spacing eligibility rate and replaying rate were reliable. The negative pressure of air suction chamber had a significant effect on plant spacing eligibility rate, and the negative pressure of air suction chamber and the diameter of suction pad suction hole of seed metering tray had a significant effect on replaying rate. The results showed that when the rotation rate of the suction tray was 20r/min, the suction chamber negative pressure was 5kPa and the suction hole diameter of the suction tray was 4mm, the qualified index of grain spacing was 95.54%, the miss sowing index was 0.50%, and the replaying index was 3.96%. .Under the same conditions, the qualified index of grain spacing was 96.3%, the miss sowing index was 13% and the replaying index was 2.4%. The optimization achieved the desired results.