The multi-entity collaborative simulation system is an important experimental system for improving cluster collaborative verification capabilities. The multi-entity collaborative simulation system can integrate multiple entity models and various collaborative algorithms to perform a full-process simulation of cluster collaboration, supporting the effective verification of collaborative system architectures, collaborative task processes, key algorithms, and hardware and software systems under typical collaborative task scenarios. This article focuses on introducing the overall design, visual generation system, collaborative simulation and testing system, and network interface design of the multi-entity collaborative simulation system. The system has been successfully applied in multi-entity collaborative simulation experiments and has passed various collaborative simulation validation assessments.