An inter-phase distance control device for charged operation on an equipotential wire is formed by connecting a wire fixing device and an insulation ruler. The wire fixing device includes an insulating yoke plate and two wire fixing grooves which are detachably mounted on the insulating yoke plate and used for fixing a lower wire sub-bus. Each wire fixing groove is composed of a mounting seat, a pulley rotationally arranged in the seat, and a self-locking protection pin detachably mounted on the mounting seat and used for preventing a wire from falling off. The insulating ruler is provided with scales used for marking length. When an operator uses the inter-phase distance control device of the utility model to walk on a wire, a lower wire of the wire on which the operator is walking changes with the sag of the wire on which the operator is walking, enough safe distance between the operator and the lower wire is ensured, and the device is simple in use and safe in operation; and meanwhile, the mounting seats are provided with the self-locking protection pins, the lower wire sub-bus can be effectively locked, the wire can be prevented from falling off when the device moves, and safety and reliability are achieved.