具有一定精度的近似解析解可以将船舶横摇运动特征直接与船体参数相联系，便于分析船体参数对横摇运动及稳定性的影响． 文中考虑阻尼力矩和恢复力矩的非线性建立了船舶在规则波中的横摇运动方程;为了克服弱非线性的局限性，采用改进的 Linds-tedt-Poincare(MLP)方法对横摇运动方程进行摄动求解，经细致推导得到精确至二阶的解析解(静水中)和精确至一阶的解析解(波浪中)． 最后对一目标船分别采用 MLP 和数值算法进行求解，验证了近似解析解的正确性．

An approximate analytical solution with a certain precision helps to construct a link between ship rolling motion features and hull parameters，which is convenient for analyzing the influence of hull parameters on the rol-ling motion and stability． In this paper，by taking into consideration the nonlinearity of damping and restoring mo-ments，an equation describing the ship rolling motion in regular waves is established． Then，in order to overcome the limitations of weak nonlinearity，the modified Lindstedt-Poincare method (MLP) is adopted to obtain the per-turbation solution of the established rolling motion equation，and the analytical solution in still water which is accu-rate to the second order and the analytical solution in regular wave which is accurate to the first order are both ob-tained． Finally，the correctness of the approximate analytical solution is verified by an example solved respectively via the MLP method and the numerical algorithm．