Abstract: A dielectric structure (10) for an electric wire or cable, presenting an inner hollow cylindrical body (2) and an outer hollow cylindrical body (3), said bodies (2, 3) being coaxial and being connected together by a plurality of spacers (4a, 4b, 4c, 14). The main characteristic of a dielectric structure is that each spacer (14) is constituted by a first curved wall (15) and by a second curved wail (16) that is curved in the opposite direction relative to a radial plane interconnecting the two bodies (2, 3), the walls (15, 16) having at least one intersection zone (17), two successive spacers (14) being in contact with each other.