Abstract: Application software V&V activities determine whether the output results are consistent with the requirements of tasks throughout each stage of application software development process, and confirm whether the ultimately generated application software is conform to its intended use and other related requirements. A set of reasonable and feasible workflow for application software V&V activities was proposed based on the characteristics of the application software in this paper, and was demonstrated with the application software V&V activities in transformation project of in-core instrumentation system (RIC) in a nuclear power plant.