Abstract: The local nonlinearity dynamic transformation reduction is developed to obtain the nonlinear dynamic responses of jointed structures in the time and frequency domains.The Newmark's integration and multi harmonic balance methods are used to con-vert the nonlinear dynamic differential equilibrium into nonlinear algebraic ones in the time and frequency domains,respectively.The dynamic responses only related to the degree-of-freedoms(DOFs)of nonlinear joints are defined as the iteration vector to decrease the dimensions of nonlinear algebraic equations.The dimensions of Jacobian matrix are consequently reduced toimprove thecomputational efficiency.The Iwan model is used to describe the local hysteresis nonlinearity of joint interfaces,and two examplesof 3 DOFs mass spring -stiffness oscillator and laptypejointed beam system are simulated to contrast the prediction precision andcomputational efficiency.The comparison result of nonlinear dynamic responses shows a good agreement with the existed methods.The proposed nonlinear dynamic reduction method reduces the computation cost of iteration process and indicates a higher computational efficiency with about 30%speedup in the time domain and 70 times speedup in the frequency domain.