Dissimilar metal welds（DMWs） formed by joining ferrite based heat-resistant steel and austenitic stainless steel（or nickel base alloy） with nickel base weld are widely used in nuclear power, thermal power, petrochemical and other industries. The early failure of DMWs often occurs under the condition of high temperature and low stress, which leads to the abnormal shutdown of the unit and brings huge economic losses and safety risks. Therefore, the early failure of DMWs has been focused by the engineering and academic circles. In this paper, the early failure of DMWs is reviewed and summarized. Firstly, the microstructure characteristics of DMWs are introduced, and the metallurgical characteristics of the region near the interface between ferrite based heat-resistant steel and weld are focused on, including martensite layer, carbon migration and type I/II carbides. Secondly, the characteristics of welding residual stress and its influencing factors are briefly summarized. Thirdly, the high temperature creep data of DMWs are summarized, aiming at the characteristics of creep fracture location transfer of DMWs, the fracture along the interface between ferrite based heat-resistant steel and weld is a significant feature of DMWs failure. This failure mode is related to strain concentration, thermal stress, matrix structure degradation, carbide coarsening and oxidation. Finally, some methods and suggestions for prolonging the service life of DMWs are given.