Abstract: During the ultrasonic testing for a forging ring, a large area rejected reflection waveforms were found on an end, but at the other end, the corresponded waveforms were not displayed, while the bottom reflection waveforms were in low amplitude. Because of the ring part was low in height and attenuation coefficient, so it was judged that there was a defect with large angle between defect extending direction and the sound beam, or there were low density defects. Fluorescence with the metallographic verification testing proved that there was a noodle folded forging cracks at the end parts and inner circumference, the crack and the incident longitudinal wave beam axis being at 61° and 45° angle. The ultrasonic testing depth of two special waveforms which located at displaying screen 20 and 33 were qualitatively analyzed, which were confirmed to be the reflection waveform of defect with 61° and 45° angle. It was helpful to identify the 61° and 45° defect and avoid the defect misjudge.