<p>Aiming at the difficulty of accurately modeling the friction slip effect in engineering calculations for multi-span continuous cable structures, it is proposed to develop a three-dimensional slip cable element USER101 by using the secondary development platform of ANSYS-UPFs combined with the catenary theory and the Euler-Eytelwein formula. Firstly, the element is cut into two two-node cable elements, and based on the principle of invariant total unstressed length, the direction function is utilized to discriminate the slip state of the cable elements at the support point. When the support point of the left and right cable end force is equal to reach equilibrium, and then through the catenary theory to find out the tangent stiffness matrix of the two cable elements, after the group set to get the tangent stiffness matrix of the three-dimensional sliding cable elements. Finally, the algorithmic process was compiled and developed by connecting the element to the ANSYS user platform. By analyzing the arithmetic examples of multi-span continuous cable structures with and without considering friction, the results show that the results calculated by the USER101 element are consistent with the theoretical solutions, which verifies the high accuracy of the element and the calculation method. By analyzing the results in the engineering examples, friction has a significant effect on the peak and distribution of internal forces in continuous cable structures, which in turn affects the deformation, and the loss of cable force increases gradually from the loading point to the ends. The new three-dimensional sliding cable element USER101 developed in this paper has no difference with the internal self-contained elements of ANSYS, and can be called at any time, which is easy to use in the actual project. It improves the computational accuracy of continuous cable structures and enhances the computational efficiency compared to other programming.</p>