Simulation Based Acquisition(SBA) gains interest from the defense acquisition community. To accomplish SBA efficiently, M&S should be collaborately used in. This paper proposes PBA(PlugIn-Based Architecture) that is a common software development infrastructure and provides reuse mechanism with plugin components. PlugIns are reuse entity possible to plug-in-play statically and dynamically. This architecture supports stand alone simulation and HLA-compliant distributed simulation also.