There is provided a transmission cable that enables an increase in the number of wires or a further reduction in the diameter while having the electrical characteristics equivalent to those of the conventional coaxial cable. The transmission cable includes four first coated conductor units, each of which is formed by a first conductor and a dielectric formed on the outer periphery of the first conductor, and three second conductor units, each of which has approximately the same diameter as the first coated conductor unit and is disposed adjacent to the dielectric. One of the first coated conductor units is disposed at the center, and the remaining six units of the first coated conductor units and the second conductor units are disposed around the one first coated conductor unit disposed at the center so as to be adjacent to each other.
