In order to understand the performance of vegetable seedling transplanting mechanism, the movement of vegetable seedlings passing through seedling system was simulated based on Pro/E and ADMAS software. The equation of displacement and velocity of vegetable seedling were deduced. A nutrient soil bowl model of vegetable seedlings and a real size model were developed. We designed the parameters of vegetable seeding transplanting mechanism by theoretic analysis and optimum parameter. The validity of the parameters was demonstrated by simulation on the transplanting mechanism. The research can provide valuable theoretical principle for the parametric design, optima design and experiment of the vegetable seedling transplanting in the future.