Abstract: This paper makes a theoretical analysis and experimental verification on the structure, principle and motion attitude of the manipulator for automatic transplanting and taking seedlings from the pot with the steering gear as the moving component. According to the specific requirements of the transplanting manipulator, the SolidWorks software is used to simplify the modeling of the seedling taking manipulator, determine the motion trajectory of the cavity tray seedling taking manipulator, obtain the relevant working parameters of the four steering gears of the manipulator, and use the MATLAB software to obtain the motion trajectory equation of the transplanting seedling taking manipulator; By comparing the experimental parameters of pepper seedling picking with the simulation trajectory obtained by SolidWorks software, it is verified that the actual value of pepper seedling picking process is close to the theoretical value, the actual value is more than the theoretical value by 1%, and the success rate of experimental seedling picking is 98%, which meets the actual transplanting requirements. Therefore, it is determined to use single chip microcomputer as the control system, The feasibility of controlling the steering gear as the moving part of the seedling picking manipulator. This study provides a new theoretical and experimental basis for the research and development of automatic transplanter for plug seedlings.