The substation application system can implement IEC 61850 communication by integrating an IEC 61850 communication module（client or server）. As the core function based on the IEC 61850 communication module is basically identical， a design scheme is proposed for developing the IEC 61850 communication module by the plug-in technique. The goal of increasing the reusability and scalability of the IEC 61850 communication module is attained by referring to the plug-in design method and adopting the dynamic chain base and dynamic negotiation interfacing mode. Meanwhile， a description of realizing the generalized IEC 61850 communication module is made， including the data structuring method and the solution for problems likely to be encountered in engineering practice. Engineering application has verified that the scheme is practical and feasible.