Abstract: In the twisting method for breakdown voltage test of enameled round wires, flashover causes systematic errors in test results. Electrode spacing and the surface condition of the sample are strongly related to flashover voltage, which affects the accuracy of breakdown voltage test results for enameled round wires. Through experimental verification and comparison of sample conditions, flashover during breakdown voltage test of enameled round wires were analyzed. Results showed that the main reason for flashover in breakdown voltage test was the insufficient electrode spacing. By reserving sufficient electrode spacing to prevent flashover, the resultant error could be eliminated.