Provided is a distribution line system replaceable in a live wire state. The distribution line system, wherein first and second electric poles are installed adjacent to each other on a ground, comprises: a first wiring unit connected to an upper portion of the first electric pole to transmit power to the second electric pole； a second wiring unit installed inside the first electric pole to supply the power to the second electric pole by underground； and a control unit. The first wiring unit includes: a frame including an accommodation space therein, and providing an opened vent on an outer surface thereof； an insulator shed protruding from an outer side surface of the frame, and having wings of a circular structure stacked to be spaced apart from each other； and a functional module including a functional material sublimated into an atmosphere and emitted outside the frame and a case for storing the functional material, and accommodated in the frame. The second wiring unit includes: a detour line electrically connected to the first and second electric poles, and buried and installed on the ground； a first connection unit connected to the detour line and the inside of the first electric pole； and a second connection unit connected to the detour line and the inside of the second electric pole. An upper cap of the case includes: a first metal layer having a first thermal expansion coefficient； a second metal layer having a second thermal expansion coefficient lower than the first thermal expansion coefficient, and disposed on an upper surface of the first metal layer； and a discharge hole for passing through the first and second metal layers. When an abnormality occurs in the first wiring unit, the control unit indirectly supplies power supplied to the second electric pole from the first electric pole through the first wiring unit, by using the second wiring unit.활선 상태에서 교체 가능한 배전 선로 시스템이 제공된다. 상기 배전 선로 시스템은 지면에 서로 이웃하게 설치된 제1 전주와 제2 전주에 있어서, 상기 제1 전주 상부에 연결되어 상기 제2 전주에
