The internal friction peaks in Al-0.5wt%Cu alloys were observed near 0℃ and 90℃ respectively under forced bending vibration within the audio frequency range and the amplitude internal friction peaks were observed at 6℃ and 90℃. It may be considered as an anomalous internal friction phenomenon showing both temperature peaks and am-plitude peaks. It is suggested that the peaks may be associated with the motion of disloca-tions dragged by point defects.