Abstract: P91/T91 steel has excellent rupture strength at high temperatures.Therefore,it has broad application prospects in power station and petrochemical enterprise.The mature melting and heat treatment of P91/T91 steel in China are reviewed from several aspects of manufacturing,welding procedure and mechanical properties,and the welding problem with homogeneous or dissimilar steel is described.The properties of P91/T91 steel meet the demand of ASTM standard ,and the creep properties are similar to ASTM standard.Fatigue properties of P91/T91 welding joints are excellent.However,the long-time high temperature properties of P91/T91 steel,especially the welding joints,need further research.