HPR1000 steam generator is the third generationa nuclear power technology which be developed independently by China.This paper introduces the structural characteristics of HPR1000 steam generator,and describes the welding materials and process requirements for its key parts. Meanwhile,the key welding processes to be implemented,such as the stainless steel cladding weld of primary head,tube sheet cladding weld,tube-to-tube sheet weld,primary nozzle safe end weld,have been introduced in detail. It lays a foundation for the mass production of subsequent HPR1000 steam generator and provides a powerful technical guarantee.