In recent years, hybrid devices have increasingly received more research.However, few of researchers studied the dynamic analysis.The inverse dynamic analysis of a novel hybrid machine tool designed in Tsinghua University is presented.The hybrid machine tool under consideration consists of parallel and serial structures, which is based on a new 2-DOF parallel platform and serial orientations.The kinematics and the dynamic equations are studied first for the parallel structure through Newton-Euler approach.And then, the dynamic analysis for serial structures is conducted.Finally, a closed-form inverse dynamic formulation is derived by using some elimination techniques.Some simulation results are also given.