The present-day software systems are increasing tremendously in size. This makes verification and validation of these systems an increasingly difficult task. Not only size of systems increases, an increasing number of features and formalism need to be developed and supported to model and analyze real-life applications. Each system is represented in the form of model. There are many modeling notations available such as BPMN (Business Process Modeling Notation), UML, BPEL(Business Process Execution Language) etc. BPMN is itself capable of representing all aspects of particular large business process. Therefore BPMN is an emerging standard for representing business processes and indirectly software systems. BPMN is visual process modeling notation which can be easily understood by business analysts. But BPMN lags behind formal semantics of systems. At the time of verification of particular system such modeling notations are not enough to give semantic correctness of system. Thus forverification and validation of systems, according to proposed approach BPMN model of system is converted into REO model consequently then into mCLR a formal specification language.