This article describes the design and development process of an online shopping website system based on ASP.NET and SQL Server. The article begins with a requirements analysis of the system, including system feasibility analysis, use case analysis, functionality and feature analysis, and operational environment analysis. Next, the article describes the overall design of the system in detail, including the introduction of system functions, the design of front‐end functions, and the database design. Subsequently, the article discusses in depth the detailed design of the system, including the implementation of the system home page, user login and registration module, search product module, detailed product information module, shopping cart module and view history order module.