Abstract:With the wide application of high performance composites in aerospace, military and other high-tech fields, more and more attention has been paid to the quality and performance inspection of composites. How to conduct Nondestructive Testing(NDT) of composites by various methods has become a hot research direction for researchers in recent years. Terahertz wave has low quantum energy and is transparent to most non-polar substances, so it has unique application advantages in the field of nondestructive testing of composites. In this paper, based on the characteristics of THz technology, the nondestructive testing of Terahertz Time-Domain Spectroscopy(THz-TDS) and terahertz imaging technology are discussed in detail, and the current development trends of terahertz nondestructive testing technology for composite materials are summarized. Finally, the development prospect is outlooked.