It’s complex to model and solve spherical 2R mechanism on the strength of given positions and attitude angles of endpoints. In this paper, the spherical 2R mechanism is synthetically studied by using conformal geometry algebra, and applied to the design of a seedling pick-up mechanism. Starting from the given key points, the range of the spherical radius where the mechanism moves was studied. The scope was narrowed down as the structural parameters of the mechanism and the interference conditions between the end-effector and the seedling tray. Then, the mathematical model of 2R were established according to the given data. The data of fixed point and rod length were calculated. Furthermore, genetic algorithm was used to select the better fuzzy point with large attitude angle in seedling pushing stage. Finally, a three-dimensional model was established through the parameters of the mechanism and verified by simulation.