The invention provides a positioning hook entering and leaving an electric field in a live mode and a positioning device, which belong to the technical field of live maintenance equipment. The positioning hook entering and leaving an electric field in a live mode comprises two hook pieces, a first connector and a second connector arranged at the upper part and the lower part of the hook piece, a limiting piece rotarily arranged on the first connector, a spring pin abutting against the limiting piece and a removing assembly for controlling movement of the spring pin, wherein the removing assembly comprises a slideway and a sliding member disposed on the hook piece; the slideway is arranged along the length direction of the spring pin and the end point is located at the pin end of the springpin; and the sliding member is provided with a hoisting assembly for connecting an aircraft. According to the positioning hook entering and leaving the electric field in the live mode and the positioning device, the aircraft is adopted to lift the hoisting assembly to transmit a pulling force to the sliding member, the sliding member slides along the slideway, the pin end of the spring pin is finally pushed, recovery of the positioning hook is realized, the operation is convenient and quick, a recovery device is not highly required, and the positioning hook and the positioning device are moresuitable for live maintenance operations.