With the development of laser technology, high laser-induced damage threshold (LIDT) is required for optical thin film devices used in high power and high energy laser systems and laser protection systems. However, at present, there are still some problems in the measurement of LIDT, such as inconsistent measurement standards, poor repeatability, poor accuracy, and difficult comparison of mutual results. The main reason is that different measurement materials and film stacks are suitable for different damage discrimination methods. In this paper, the research on damage identification method are summarized, and the image method, scattering method, plasma flash method, plasma spectrometry and so on a variety of different damage identification method are presented, the principle and characteristics of various methods, as well as the effect of damage criterion, the research on laser damage threshold test work are described in this paper. It is expected to be a reference for the research work of LIDT test.