A method for the nonlinear dynamic analysis of inelastic framed structures subjected to large displacements is presented. The nonlinear behavior of inelastic steel plane frames with or without initial geometric imperfections is also studied. The proposed method for dynamic analysis is based on an incremental form of equations of motion of the structures. A previously proposed member tangent stiffness matrix of an inelastic member is extended for dynamic analysis. Newmark's β-method is used as the numerical integration technique for solving the incremental form of the equations of motion. The feasibility of the proposed method is illustrated by several numerical examples on the dynamic analysis of inelastic frames.