To solve the problem that drift error cannot be eliminated by the traditional incrementaliterative algorithm in nonlinear damage analysis, an accurate incremental iterative algorithm namely secant stiffness-additional load method (SSALM) is proposed. In the method, the incremental equilibrium equation is established by using the secant stiffness matrixand additional load in the algorithm. Then, a new incremental-iterative algorithm is establishedcombining the incremental equilibrium equation with the arc-length approach. The results indicate that the SSALM can accurately capture the real equilibrium path of structure and effectively correct the drift error.