With the integration of cutting-edge technologies such as information communication, the internet, big data, cloud computing, and artificial intelligence into intelligent vehicles, the scale and complexity of their cyber-physical subsystems have been steadily increasing. In response to the growing demands for high concurrent access and efficient operation within the multiple entities of information system modeling and simulation, this study introduces a novel method for multi-entity co-simulation of intelligent vehicles, grounded in distributed message-oriented middleware. Tailored for the unique challenges of multi-entity co-simulation scenarios, the proposed method involves classifying heterogeneous simulation platforms and developing distinct implementation modes for message middleware interface units corresponding to each platform type. This approach significantly enhances the efficiency of multi-entity co-simulation in intelligent vehicle systems, facilitating more effective integration and operation of diverse subsystems.