AbstractIn the case of nonproportionally damped structures, the forced decoupling method is often adopted in approximate analysis. However, it generally cannot satisfy the precision requirements for practical engineering. Taking this into account, methods to calculate the stochastic seismic response of nonproportionally damped structures are systematically studied in this paper. Based on the pseudoexcitation method, an efficient and accurate iteration method with the advantages of high computational efficiency and iteration convergence is also proposed. This new method is preferred for practical engineering because of real expressions. Finally, a numerical example is carried out to verify the properties and advantages of the proposed method.