In the ubiquitous era, it is necessary to research the architectures of multiprocessor system with high performance and low power consumption. A simulator developed in high level language is useful because of its easily changeable architecture, which includes application-specific instruction sets and functions. In this research, the basic framework for multiprocessor simulator system was constructed based on a multiway cluster. Furthermore, this paper proposes and implements a double-buffered communication model to improve communication speed keeping independence from each processor model on the system. This model shows over 50% system performance improvement rate compared with the basic framework integrated with the single-buffered model. As the conclusion, the improved simulator system is suitable for the research of heterogeneous multiprocessor system.