Due to its complicated spatial structure and force, the conventional influence matrix method is re- stricted to some extent in the process of secondary cable adjustment of the suspender force of long-span basket handle arch, inconsiderateness is apt to occur. By using a 450 m long-span basket handle arch as the engineer- ing background and increasing the weighting coefficient of the influence matrix, this study solved the weighted least-squares solution of equation through Matlab. After a small amount of iterative computation, the cable force difference was stable and the maximum relative error between the calculated cable force and the designed cable force was 0.28%. As a method of accelerating convergence with homogeneous rate of convergence, the weighted influence matrix provides a new way for determining the cable force of similar bridges in the completion stage or the secondary cable adjusting.