Abstract: During the ultrasonic test, the AgCuV alloy conductive slip ring was found to have internal defects. The causes of defects were analyzed by means of chemical composition analysis, ultrasonic test, metallographic examination, scanning electron microscope and energy spectrum analysis. The results show that the internal defects of the AgCuV alloy conductive slip ring were cracks. The brittle second phase with vanadium made the binding force between brittle second phase and AgCu alloy matrix weak, and microcracks appeared at the stress concentration. The microcracks propagated along the part with weak bonding force between the second phase and the matrix, which eventually led to the formation of internal defects in the AgCuV alloy conductive slip ring.