Solid thermal finite element model of suspension bridge main cable was established by finite element software ANSYS. Layered grid was divided along the radial direction of main cable. Main cable thermal parameters, including heat conductivity coefficient, specific heat, thermal expansion coefficient were fitting with least square method. Three-dimensional transient temperature field of main cable was simulatd based on the thermal parameter fitting results. Main girder and tower of the suspension were made up of beam element. Solid thermal model of main cable was connected with suspension bridge for that degree of freedom of main cable was consistent with that of main girder and tower. This model can accurately simulate the uneven temperature field of main cable under fire scenario and calculate elastic modulus, tensile strength under high temperature.