In order to reduce the power consumption during the hole-forming operation and the amount of soil returned to the hole during the hole-forming process, this study was performed to find optimization of the parameters of the soil opener for rapeseed pot seedling transplanter. Analysis of the trajectory and force of the soil opener was used to determine the factors affecting the external dimensions of the molded hole and the power consumption of the hole-forming operation, and the bottom size of soil opener, the angle of entry soil and the soil opening depth were selected as the influencing factors. The parameter ranges and the multi-objective optimization simulation test through the single-factor and multi-factor tests were used to establish a mathematical model of the soil entry resistance of the soil opener and the rate of the soil return of the hole section to get the influence law of each parameter of soil opener on the quality of hole-forming operation and the optimal parameter combination. The results of the simulation tests showed that the factors affecting the soil entry resistance in the order of predominance were the soil opening depth, the angle of entry soil, the bottom size, while the factors affecting the rate of the soil return of the hole in the order of predominance were the angle of entry soil, the soil opening depth, and the bottom size. The optimal combination of parameters for the soil opener was the bottom size of 39 mm, the angle of entry soil of 20.5° and the soil opening depth of 60 mm. Using the hole-forming device test bench to verify the effect of hole-forming operation, the results showed that the relative errors of soil tank test results and the simulation values for hole opening diameter, effective depth, soil entry resistance and the rate of the soil return of the hole were 7.7%, 3.7%, 4.5% and 8.3% respectively, and the holes formed satisfied the requirements of potting seedling transplantation, which verified the accuracy of the constructed model and the optimized parameters.