In this study, in order to verify the effectiveness of the flaking inspection by the combination of infrared thermography and ultrasonic testing technique method which seems to be able to efficiently inspect the flaking of concrete, this paper compares and evaluates flaking detectability and quantitative evaluation experimentally using a concrete test piece with artificial defect. As the result, the infrared thermography was effective as a screening technique of the flaking, because it can quickly inspect the wide range, and the ultrasonic testing technique method seemed to be effective as a detailed inspection technique as a depth measuring means of the defect detected as the flaking by the screening.