To easily fold a flat circuit body on a plane which is coplanar to an arrangement plane for arranging a plurality of conductors, and to produce it at a low cost.

In this flat circuit body 1, provided with a flat cable 2 with its plurality of conductors 4 arranged in parallel with a prescribed space, and integrally coated with an insulator 5, a plurality of unit cable parts 7, having slits 6 formed in the insulator 5 between the conductors 4, are held each other in a state of being folded in a prescribed direction, in a plane coplanar to the arrangement plane for the conductors 4, and a terminal of the each unit cable part 7 is connected to each connector 3.