In order to obtain the optimum operating parameters for the dibbletype planting apparatus of vegetable pot seedling transplanter in highspeed condition, a testbed with adjusted parameters was designed and a soil trough experiment was conducted for seedling transplanting. A central composite design method of second order regression orthogonal rotation was carried out with transplanting speed, characteristic parameter and oblique angle of dibble as experimental factors and with qualification ratio of perpendicularity, variation coefficient of planting spacing and qualification ratio of planting depth as response values. By using SAS 9.1 regression analysis method and response surface method, both single factor and interactive factor on response values were analyzed. Combined with nonlinear optimization calculation method, the structural parameters and working parameters were calculated optimally. The results obtained in the condition of high transplanting speed (90 seedlings per minute) indicated that, in terms of significant degree, the influence factors of qualification ratio of perpendicularity were oblique angle of dibble, characteristic parameter and transplanting speed; the influence factors of variation coefficient of planting spacing were transplanting speed, characteristic parameter and oblique angle of dibble; the influence factors of qualification ratio of planting depth were transplanting speed, oblique angle of dibble and characteristic parameter. The optimum parameter condition of the dibbletype planting apparatus after optimizing was 0.47m/s of transplanting speed, 1.18 of characteristic parameter and 87° of oblique angle of dibble. At this time, qualification ratio of perpendicularity achieved theoretical optimum value of 98.01%, variation coefficient of planting spacing was 5.93%, and qualification ratio of planting depth was 89.25%. Through verification by an experiment in optimum condition, the experimental value of qualification ratio of perpendicularity was 96.6%, variation coefficient of planting spacing was 6.1%, and qualification ratio of planting depth was 87.8%, which indicated that the experimental results and predicted results were consistent, and regression models established by the experiment were appropriate. According to comparison of transplanting performance before and after parameter optimization, qualification ratio of perpendicularity and qualification ratio of planting depth increased by 5.8 percent and 3.6 percent respectively, and transplanting performance was superior to the technique indexes of national and industry standards as well.