Application of SAP business solutions to enterprise is the one of most important method of enterprise informatization.It makes use of SAP built-in optimum industry solutions as main functions of ERP, and provide custom function with the configuring parameters or a small quantity of secondary development in SAP, so as to realize ERP of highly integrated and full functions. Based on putting SAP SD into use in large copper smelter, the paper presents sales process, SD description and terminology, system design, implementation and underlying technology, supporting MES and so on. The summary about online-use is also given in the end of the paper.