In this paper, the method of making report is put for ward and applied to developing hydrology data process software. The basic thought is: to abstract a serial basic element from the report; to use the representa tion style of element in XML(extensible markup language); to build the title, head, data, tail and assistant information of the report made by the basic elements; and then to form the report. At last, the XML report is resolved and the making and output of the report can be implemented by using the database technology on the visualized platform VC++. The research result show that the problems of data complexity and rigorous format are solved in making report of hydrology data process , which can meet the need of the press of a hydrology almanac.