The objective of the paper was to expound the main process of metadata technology and method applied in the construction of soil and water monitoring information system. Firstly the paper defined contents of rectadata, including basic metadata and business metadata, among of them, the basic metadata were used to manage the data stored in the database and mainly to describe the information about data, and the business metadata helped system to implement the function of update and inquiry of data. Secondly the paper expounded in details contents and purposes of two types of metadata and described how to organize and store these metadata. Finally, the flow chart of management of metadata was proposed, and functions of creation and management of metadata were integrated into the management and update system for information platform, then the synchronous management for metadata and their data was realized for the system.