Abstract: Most of expert knowledge in agriculture is descriptive and experiential, so it is difficult to describe in mathematics and build decision support system for greenhouse. Therefore, the decision support system for greenhouse constructed with data warehouse and data mining technology was introduced in this paper. In the system, data warehouse was founded to memorize diversified data, and the use of on-line analytical processing and data mining enriched knowledge base with new agriculture information. Implementation of system adopted SQL Server analysis, as a result, tightness coupling of data warehouse, data mining and application, improved the efficiency of data mining. Combined with data warehouse, on-line analytical processing (OLAP) and data mining were adopted to construct a novel decision support system.