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Aiming at the inaccuracy of fertilizer location in potato planter popularized in China, combined with the distribution law of potato root system and the planting pattern characteristics of one ridge two rows for potato, and the separated layer fertilization technology based on surface drainage and V type anti blocking structure was proposed. The design and analysis of separated layer fertilization furrow opener and a depth adjustable separated layer fertilization furrow opener was developed. The motion relationship between the soil and furrow opener was studied, and the movement process of fertilizer on curved surface fertilizing plate was analyzed. The variation coefficient of the stability of the lower layer was experimented by single factor bench test, and the optimum working length of groove wheel was 50mm. Under the condition of optimum working length of groove wheel, the quadratic universal rotary assembly experiment of two factors were carried out with the rotation speed of manure shaft and the curved surface angle of fertilizing plate as experimental factors, the variation coefficient of the stability of left and right sides for upper layer fertilizing box as experimental index. The saliency analysis of regression equation and parameter optimization were obtained by using the DPS and Matlab software. The results showed that the rotation speed of fertilizing shaft of 20.5r/min and the curved surface angle of fertilizing plate of 15° were the best combination factors, which led to the variation coefficient of the stability of left and right sides for upper layer fertilizing box of 3.30%. Five repeated experiments were carried out under the optimal parameters. The results showed that the average variation coefficient of the stability of left and right sides for upper layer fertilizing box was 3.71%, and the experimental value was similar to that of the theoretical value. Meanwhile, the field performance experiment showed that the performance of separated layer fertilization furrow opener completely met the relevant standards of potato planting.