The work aims to analyze the change of the robot's workspace when different length values of linkage 2 (l2) and linkage 3 (l3) and different joint rotation angles θ3 of l2 are taken. The linkage coordinate system of the robot was established. The kinematics equation of the robot was established in D-H method according to the linkage parameter table. Based on the kinematics equation, Matlab was used to simulate the workspace. After changing the lengths of l2 and l3 as well as the joint rotation angle θ3 of l3, the comparison chart of the xOy and xOz planes of the robot’s workspace was obtained when different linkage parameters were taken. And the boundary of comparison chart was drawn after inserting the comparison chart into the AutoCAD. The change in the simulated plane figures was studied by analyzing the change in the boundary of the comparison chart. The simulated projection drawings of xOy and xOz of the robot’s workspace were acquired when different parameters were taken. When the linkage parameters are different, the workspace will differ accordingly, which lays a foundation for linkage parameter optimization and motion control of the robot.