Abstract: Through summarizing the achievements and the development stage of GIS interoperability,analyzing the contrast of traditional distributed technique to Web Services technique,abstracting tow modes of GIS interoperability (interoperating mode based on direct accessing and interoperating mode based on common interface),this article pointed out that the ideal method for interoperation was the interoperation mode of common interface based on Web service. Then this article described the structure of the method and expounded the key techniques of the method. At last this article reached the conclusion that Web service was fit for space information,interoperating and integration.

Key words: GIS interoperability, distributed GIS, Web service