Abstract: Aims at meeting the fertilization requirement of 4-row rape transplanter, a collecting and discharging device was designed. The single factor and response surface experiments were conducted to study the groove width, outlet width and rotary speed, which influenced the variable coefficient of total displacement stability and consistency. The results of single factor test showed that the device achieved design requirement when groove width was 15-25 mm, outlet width was 15-25 mm and rotary speed was 40-50 r/min. The results of response surface test showed that the best combination was groove width of 19.61 mm, outlet width of 20.74 mm and rotary speed of 45.3 r/min, and the variable coefficient of total displacement stability and consistency was 3.89% and 8.17%, respectively. Experimental results showed that the performance of fertilizer collecting and discharging device could basically meet the national machinery industry standard requirements for multiple lines fertilizer discharging devices, and fertilizer collecting and discharging device had certain significance.