The invention discloses an AVC automatic switching system for a high-voltage chamber. The system comprises infrared ray devices, an AVC automatic switching device, an AVC automatic switching device controller and an alarm device, wherein the infrared ray devices are installed on a front door and a rear door of the high-voltage chamber and used for monitoring personnel access of the high-voltage chamber, the AVC automatic switching device controller forms a star network structure with the infrared ray devices and judges the number of people entering and exiting the high-voltage chamber, the AVCautomatic switching device controller controls the alarm device when a single person enters the high-voltage chamber, and the AVC automatic switching device is controlled to switch in or out an AVC function according to the condition whether the person enters or exits the high-voltage chamber. The system can realize AVC automatic switching according to personnel access of the high-voltage chamber, improves the working efficiency, and effectively reduces potential safety hazards to the power grid and people.