Abstract: In the system simulations based on VC，one way to display real-time and dynamically simulation results is developing an ActiveX control with scope display function.The control is seamlessly embedded in program to set up a compact and beautiful interface，which also supports encapsulation and issuance for other types of project applications.The paper introduces some key technologies about developments of the scope display control on MFC of VC and gives an application in the simulation of a target tracking system.The control can help people analyzing of the whole variational trend of numerical values to understand and mastering the simulation procedure.