The invention belongs to the technical field of electric power transmission and transformation equipment detection, and particularly relates to a voltage application lead and a cable head holder for withstand voltage test of high-voltage electrical equipment. A lead clamp bolt at the lower end of the lead clamp is in internal thread connection with a detection device at the upper end of a leakage current self-detection device, a detection device bolt at the lower end of the leakage current self-detection device is in internal thread connection with a supporting bar at the upper end of a telescopic insulation supporting bar, internal threads of the lower portion of a supporting rod at the lower end of the telescopic insulation supporting bar is in screwed connection with a base plate bolt of a magnetic base plate, and the magnetic base plate is fixedly sucked to a casing of the equipment. The lead and the holder for withstand voltage test of high-voltage electrical equipment solve the problems that failure of voltage application and damage to equipment due to the fact that the voltage application end discharges to the ground or is grounded due to improper fixing of leads and cable heads in the withstand voltage test are solved, and the working efficiency and safe reliability of the withstand voltage test are improved.