With the rapid development of nuclear power industry in china,it is imperative to make nuclear power technology and equipment independence,it is necessary to design and manufacture nuclear power equipment independently. For CPR1000,on the basis of the original foreign design,though the introduction,digestion,absorption of domestic design units,the process optimization of domestic manufacturing plants,the experimental development of domestic material suppliers,boron injection tank self-design and independent manufacturing have been realized. In this article,analyzing the chemical component and mechanical property of 20 MnHR of domestic material for boron injection tank and experimenting the property of welding,actualize welding procedure qualification under welding property analyzing,thus the qualified welding procedure specification can be worked out to carry out welding,which can be used in the manufacture of boron injection tank in nuclear station,the welding of domestic material 20 MnHR for boron injection tank can be completed and the independence and localization of boron injection tank can be realized.