Abstract: Formation of welding solidification crack was a high-temperature complex process affected by many factors. Although remarkable research was achieved, there were still some theoretical and technical problems. Research progress in the field of welding solidification crack was reviewed in the paper from aspects of mechanism of solidification crack, criterion for solidification crack and susceptibility test for solidification crack. In the research of formation mechanism of welding solidification crack, strength theory, liquid film theory, intergranular bridging theory and solidification compensation shrinkage theory were formed. Research on susceptibility criterion of solidification crack was mainly based on three aspects of stress, strain and strain rate to form a variety of criterion models. Testing methods of solidification cracking susceptibility were compared and analyzed. Advantages of transverse moving weldability (TMW) as a new testing method were pointed out. Research direction of solidification crack was also prospected, which could provide theoretical basis and technical support for the in-depth study of metallurgical mechanism of solidification crack and engineering application of controlling solidification crack.