Agricultural robot technology can reflect the level of a country’s agricultural mechanization, and the level of agricultural mechanization is an important indicator of a country’s level of agricultural modernization. At present, the agricultural robots in China have made great progress. Taking an agricultural robot as the research object, and the robot kinematics method was used to analyze the relationship between various joints, including the analysis of positive kinematics and inverse kinematics. Firstly, threedimensional software was used to design the structure. According to the structural characteristics of the robotic arm, the D-H method was used to establish the link coordinate system. The relationship between two adjacent links was represented by a homogeneous transformation matrix, and the positive kinematics equations with joint variables as input were obtained. Based on the positive equation of motion, according to the structural characteristics of the robot arm itself and the actual working conditions, the constraints were set, and inverse kinematics analysis was performed by using the inverse transformation method. The analytical expressions of the joint variables were obtained. The results of the calculations of positive kinematics and inverse kinematics were mutually verified. The simulation model of the robotic arm was established by using Adams simulation software. The kinematics simulation was performed. The simulation results were in accordance with the theoretical calculations, and the correctness of the solution results of positive kinematics and inverse kinematics was verified. The research results provided a theoretical basis for followup trajectory planning of agricultural robot control, which laid a foundation for the intelligent operation of agricultural robots.