Abstract: In order to ensure quality and safety of vegetables and good health of consumers, a web-based monitoring system for detecting pesticide residues in vegetables in practice was developed based on Web with .NET platform and Structured Query Language technology. Data acquisition and processing can be realized through data statistics and web-based report forms.The structure design scheme, key technology and primary methods for achieving the pre-designed function of the system were given. The test results of the system in Jiangyin of Jiangsu Province show that application effect is good for data analysis and prediction, which can be used in quality detection and safety management of agricultural products.