Abstract: Aeroengine blade is the most important part of the engine. Severe working environment makes it easy to crack. Aeroengine blades have complicated surface structures that make it hard for traditional NDT technology to inspect. The ultrasonic infrared thermographic technology was used to detect the cracks. A series of research on ultrasonic infrared thermography technology was carried out. This paper discussed the principle of ultrasonic infrared thermography technology and the inspection system setup. The detection of fine cracks in guide blades and working blades of aeroengine is realized, and the ability of detecting cracks in aeroengine blades is demonstrated.