Composite materials are widely used in general aircraft, with usage rates exceeding 90% in various types of aircrafts. Therefore, defects in composite materials can severely affect flight safety. This paper designs an accurate defect detection method for aircraft composite materials based on infrared imaging detection technology, as well as a prototype non-destructive testing system. The non-destructive testing system consists of a data acquisition system, signal source group, infrared thermal imager group, and infrared image processing reconstruction system, which can identify the type and planar size of defects in the aircraft composite material structure and accurately locate the depth. A light-excited infrared imaging detection system for aircraft composite materials was built, and detection experiments were conducted on composite materials at different temperatures, with research results provided. These research results will expand the application scenarios of domestic infrared non-destructive testing technology, and the commercialization of research findings will be beneficial in solving maintenance and repair issues during the general aviation of aircraft.