Abstract: In multi-robot collaboration operation tasks, its movement flexibility is related to the holistic movement performance of a collaborative system, which reflects the multi-robot coordination operability, and is very important to the coordinated motion planning of the system. Using a collaborative system of three robots, D-H kinematics model of each manipulator is established, and its collaboration space is obtained through Monte Carlo method, with leveraging the operability index for system flexibility assessment, the mathematical evaluation model to check the flexibility of the multi-robot collaboration system is developed, and MATLAB is used to simulate and analyze the flexibility of the multi-robot collaboration system to obtain its visual distribution. By analyzing the distribution of flexibility in the collaborative space, a suitable coordinated operation space is determined to ensure the optimal flexibility of the multi-robot collaboration system when operating tasks.