The utility model discloses an insulating tool warns retaining ring belongs to transmission line live working technical field, including the ring, the ring is inside to be inlayed has the battery, light sense distance member, the warn light belt and the bee calling organ that warns, and the light belt of warning includes at least 1, and light sense distance member, alert light belt and the bee calling organ that warns are connected to the battery, and light sense distance member holds the position to the operation personnel and carries out the sensing, and when being close or surmounting safe distance, the operation personnel are reminded with the mode of flash of light to the light belt of warning, and the bee calling organ that warns simultaneously sends alarm sound, when the light sensing was in suitable safe position apart from the subassembly sensing to the operation personnel, the light belt of warning also can be reminded with the mode of flash of light, adopts multiple warning mode to remind operation personnel and charged body to keep suitable safe distance to effectively prevent the emergence that live working is dangerous, have the characteristics of simple to operate, strong adaptability, removable design simultaneously, can extensively be used for all kinds of action bars and insulating tool.