In order to improve the planting efficiency of planting mechanism, a high speed duckbill planting mechanism with variable catchseedling attitude for the seedling pickup mechanism was proposed. Sheep horn pepper seedlings were taken as the objects of seedling planting. The kinematics model of the mechanism was established. Its optimization goal was established, and the visual auxiliary analysis software was developed by using Visual Basic 6.0. The parameters to meet the requirements were optimized and the “water droplet” theoretical trajectory was formed. The threedimensional modeling was performed for the kinematics simulation testing which was carried out by ADAMS. The angle and speed curve of duckbill planting mechanism was analyzed to verify the rationality of the design for the seedling planting mechanism. Threedimensional printing technology was used to process some parts, and the highspeed photography bench test was carried out on the physical prototype. The correctness and feasibility of the theoretical model were verified by comparing the theoretical trajectory, simulation trajectory and actual working trajectory. The experiment showed that the average good qualified rate of planting was 99.8% and the average planting depth qualified rate was 99.2%. This verified the practicality of the mechanism and provided a theoretical basis for the cooperation between seedling planting and seedling pickup mechanism.