Abstract: Cyber net system is a subclass of Petri nets,which has the characteristic of nonlinear relation and a powerful modeling capability．A kind of computer modeling tool (CyberNetTool) was developed by using visual programming platform Visual Studio .NET．Users can interactively build Cyber net system model and use the PNML format file to store the model．Software core classes were designed to facilitate the interface controls management and model analysis．Implementation algorithms for property analysis modules and dynamic simulation module were described in detail．Finally,an application example was illuminated to show the correctness and availability of this tool.

Key words: Petri nets,Cyber net system,Modeling,PNML