This paper presented a method for SOAP message analysis based on SOAP extension. The paper discussed the method of SOAP message analysis using MSSoapT. Firstly, it introduced realization mechanism of SOAP message analysis using SOAP extension, then mainly analyzed key technologies how to realize SOAP message analysis using SOAP extension, gave a instance of SOAP message analysis in .NET. The results show that Implementation of the method for the design and verification of Web services security strategy provides an important adjunct.