VEHICULAR CIRCUIT BODY

A vehicular circuit body includes a plurality of control boxes, a trunk line that connects the plurality of control boxes to each other, and a branch line that directly or indirectly connects the control box to an accessory. The trunk line and the branch line each includes a power source line having a predetermined current capacity and a communication line having a predetermined communication capacity. Each of the plurality of control boxes includes a plurality of branch line connection portions to and from which the communication line of the branch line is attachable and detachable. Each of the plurality of branch line connection portions is provided with a lock function portion that is physically or electrically brought into a lock state in a case where the branch line is not connected thereto.