Abstract: Based on B/S,a welding process expert system had been developed for pressure equipment manufacturers according to NB/T47014—2011,NB/T 47015—2011,TSG Z6002—2010 and so on. Information query module and welding process design module were designed in the paper. It is very convenient for users to query,add and modify the information of the chemical composition,mechanical properties and physical properties of steel and consumables,and the information of steel’ s weldebility. The welding process design module was designed according to the welding standard of the pressure equipment,and which incorporated the welding experience of the pressure equipment manufacturing enterprise for many years. The user can easily and conveniently prepare the welding process by inputting the initial conditions.