Abstract: Based on the system model language and high level architecture, a new approach of openended collaborative modeling and simulating is proposed for virtual prototype of complex systems. The new approach has the advantage of multidiscipline models integration and co-simulation in VPCS. In this approach, VPCS is divided into top model, federation model, and field component model. The scheduling mechanism of VPCS is analyzed. A virtual prototype of the flight control system of an unmanned aerial vehicle is carried out with the proposed approach. The simulation results demonstrate that the new approach can be effectively and efficiently used for modeling and simulation of multi-level, multi-granularity and multi-field VPCS.