The utility model discloses an electric power security warning device comprising an infrared detection mechanism, a flash mechanism and a power supply, which are disposed in a shell and further comprising a fixing mechanism disposed on the shell. The infrared detection mechanism is connected with the flash mechanism through a controller. The infrared detection mechanism, the flash mechanism and the controller are connected with the power supply. When the human body gets close to the infrared detection mechanism in unprofessional operation, the infrared detection mechanism triggers the flash mechanism and the flash mechanism emits hard light similar to that from a flash lamp of a camera, so that people getting close to an electrified body enters an activated state because of the flash of the hard light and further judges whether the action is safe and reasonable or not. Therefore, the habitual unprofessional operations which occur because of fatigue caused by long-time work of workers can be prevented, the personal safety of the workers and the safe and stable operation of electrical equipment and a power grid are guaranteed and the power supply reliability is improved. The electric power security warning device is simple and practical, is low in cost and small in size and is high in safe reliability.