Abstract: On the basis of Web techniques and Object Oriented Programming(OOP) concept, according to the characteristics of crop growth and development, a structural scheme of simulation system was designed. Making use of ASP.NET framework and Visual C# language, a Web-based simulation system for greenhouse crop growth and development was primarily realized, which could be used to simulate the growth and development of greenhouse crops such as tomato, cucumber related to the process of photosynthesis, dry matter accumulation and distribution, etc.