Abstract: In order to improve the visualization and interaction of agricultural machinery parts design, it introduced the virtual reality language VRML and Java programming language into the virtual display system of parts design. And it designed the three-dimensional network database system of agricultural machinery parts based on Web. The system can design the process of parts’ three-dimensional modeling, virtual assembly, design checking, processing simulation and parameters into the database for user’s convenience and browsing on the user side of Web browser. Finally, the tractor assembly and verification are taken as an example to verify the system. The test results show that it can successfully display the assembly of agricultural machinery in the form of the three-dimensional modeling network database system of agricultural machinery parts based on Web technology. In order to improve the design optimization effect of the parts, it checked the interference and mechanical strength of the assembly.