In response to problems of poor seed cutting quality and low degree of automation in seed potato cutting machine,based on the design idea of integrating seed cutting agronomy and agricultural machinery, an automatic cutting device suitable for seed potatoes was developed. The seed potato sorting and positioning were completed by sorting-positioning conveying mechanism, and the seed potato cutting process was completed by the combination of the clamping-picking and cutting mechanism. The machine was controlled by PLC to realize the cutting action process and realize the automation of the cutting process. Combined with typical seed potato geometric size parameters, the key structure design of the seed potato cutting device was completed, the process of seed potato cutting was theoretically analyzed, and the main factors affecting the seed potato cutting effect and the value range of each factor were clarified. The qualified rate of seed cutting and blind rate of seed cutting were taken as evaluation indexes, and the center distance of round table roll set, chain conveying speed and V-shaped cutter angle were taken as experimental factors. The response surface test of three factors and three levels was conducted. The analysis of variance and interaction of the test results were conducted by Design-Expert 12.0.3 software. The optimal parameter combination conditions of the test were determined by optimizing the module design of the software, and the seed potato slices were verified under the optimal parameter combination conditions. When the center distance of the round table rolls was 101.60mm, the chain conveying speed was 0.019m/s, and the angle of the V-type cutting tool was 49.50°, the qualified rate of seed cutting was 97.56%, the blind rate of seed cutting was 1.27%, and the relative error with the optimized value was less than 5%, which indicated the optimized parameter combination had high reliability and can meet the requirements of potato seed cutting.