At present, manual coding is usually used in the development of B/S architecture program. Because of the great similarity among the modules, some repetitive copy and paste work is often done in the development process. In view of the shortage of the traditional development pattern, such as long cycle and low efficiency of project development, this paper proposes a design and implementation of B/S architecture code automatic generation system. This paper introduces the related technologies used in this system and elaborates the function of each module of this system. This code automatic generation system defines a rule for describing information entity. By the file parser, the attributes of the entity are obtained. The parsing result input into the data model then database of target system is generated. The parsing result input into the template model to generate the code of target system. Thus the automatic generation of the whole target system is completed, and this code automatic generation system can reduce the development cycle of project and improve the development efficiency