The stress inside and outside the traditional cross-section combined angle steel of power transmission lines are uneven, which results in the deviation between the actual carrying capacity and theoretical design value. The double-angle steel splicing is proposed to improve the mechanical behavior of cross-section combined angle steel. Stress analysis on two splicing forms of cross-section combined angle steel was carried out with finite element simulation, so as to compare two different forms’ the coordination of component displacement, stress evenness, and stress status of the maximum stress control section. The results show that the displacement compatibility and the bearing capacity in double-angle steel splicing form are better than those in the single-angle steel splicing form, especially for towers with different height legs, in which the maximum stress of the main material of two splicing forms on the control section is 4.7% and 13.7%, respectively.