There is a great demand for strain clamp in transmission lines, but the strain clamp failure occurs frequently, which not only brings economic losses, but also seriously threatens the reliable operation of power grid. In order to explain the failure mechanism of hydraulic strain clamp and improve the safety of transmission lines, scholars at home and abroad have carried out a lot of research. Overheating and fracture engineering failure types of hydraulic strain clamp are reviewed from the aspect of failure accidents, the failure mechanisms of two engineering failure types are reviewed from the aspects of engineering analysis and mechanism research, and the influence of process parameters on failure forms is reviewed from the aspects of crimping process research. The research status of quality testing of strain clamp is summarized from the perspectives of routine testing and nondestructive testing. Finally, based on the current research status of partial qualitative analysis on the engineering failure of the strain clamp, the prospect of further research on the failure mechanism of the strain clamp is proposed.