In this paper, the proposed idea of producing fully-enclosed composite cable with CFRP coupling of high-tensile steel wires and the forming technology of the fully-enclosed composite cable body were introduced. The coordination mechanism of the fully-enclosed composite cable, the requirement of equal elastic modulus between high strength steel wire bundle and CFRP were investigated theoretically. We have come to the follwing conclusions: (1) Carbon fiber has the same strain with the high-tensile steel wire under the tension of whole anchorage. (2) The distribution of the force of the composite cable is in accordance with the axial stiffness between the carbon fiber with high-tensile steel wire. (3) To achieve a good synergy between the carbon fiber with high-tensile steel wire, similar or equivalent elastic modulus is required. (4) The stress ratio between carbon fiber and high-tensile steel wire in the fully-enclosed composite cable in engineering application should be controlled around 0.5.