Abstract: Aviation composite materials, with their advantages of lightweight, high specific strength, high specific modulus, and fatigue resistance, have become core structural materials for weight reduction, efficiency improvement, and performance enhancement in new-generation civil and military aircraft. However, composite materials are prone to defects such as delamination, porosity, fiber folds, and debonding during their preparation and service processes, posing serious threats to flight safety. Ultrasonic nondestructive testing, characterized by strong penetrability, high sensitivity, intuitive imaging, and wide applicability, has become the mainstream technology for defect detection and quality evaluation of aviation composite materials. This paper systematically reviews the typical defect types and acoustic characteristics of aviation composite materials, summarizes the principles and research progress of mainstream technologies such as traditional ultrasonic testing, phased array ultrasound, air-coupled ultrasound, laser ultrasound, and ultrasonic guided waves, and compares the advantages and applicable scenarios of each technology. It focuses on advanced imaging algorithms such as full-focus imaging, 3D visualization, and tomographic imaging, as well as the application of artificial intelligence in defect identification and quantitative characterization. It summarizes the current challenges faced by these technologies in terms of adaptability to anisotropic materials, complex structure inspection, quantification of micro-defects, and high-temperature/in-service monitoring, and looks forward to future directions such as multimodal fusion, intelligent perception, digital twins, and standardized evaluation. The aim is to provide a comprehensive reference for the engineering application and innovative research and development of ultrasonic nondestructive testing technology for aviation composite materials.