Structural strand ropes are used for suspenders and components of main cable, having a complicated stress distribution because of the twisting shape of helical wires and complicated contact problems between wires. Although these characteristics inevitably exist, cable members are generally treated as truss members that transmit only axial force in design. However, axial stress distribution and load sharing mechanism on the cross-section of wires should be required to judge accurately whether the maintenance should be conducted. As a fundamental study to solve the problem, this paper conducted 3D-FEM of a 1 × 7 strand rope to elucidate the axial stress distribution and load sharing mechanism on the cross-section. Then, a beam theory model was proposed to estimate each wire’s axial stress and load-sharing ratio, whose estimation error to FEM remained lower than five per cent.