In this paper, corona-resistant enamelled round wires were selected as test objects, different twisted wire samples were prepared, and the effects of the sample pitch, the load applied to the wire pair, and number of twists on their corona resistant life were investigated. The results show that a longer twist pitch may lead to shorter failure time, while increasing the load will significantly extend the failure time of the sample, and the effect of different number of twists on failure time of the sample is not obvious. After being soaking in sodium chloride solution, the failure time of the sample slightly extended. However, as the concentration of the solution further increases, the change in failure time is relatively small. After the steel ball used for clamp the sample conductor is subjected to long term corrosion, during the corona resistance test, the exposed conductors of the sample will exhibit more severe electrochemical corrosion characteristics, resulting in a significant increase in the right-skewed extreme value in the failure time data. Based on the above research, when preparing twisted wire samples of enamelled round wires, the twist pitch and load should be precisely controlled, and the steel balls should be regularly replaced according to the testing frequency, to ensure the consistency of corona-resistant test results.