In order to identify joint contact dynamic parameters of 3 DOF flexible joint manipulators, a vibration and movement coupled modeling approach of the manipulators was proposed. Combining the traveling wave approach of structure and the rotation transformation matrix of joint, the waveguide equations of mechanism were established. Considering the conditions of the general force balance and displacement boundary of each joint, vibration excitation of the system in moving states were obtained. Vibration equations were achieved according to the derived vibration torques and torsional vibration angles. The contact dynamic parameters of joint surface can be identified by using the vibration and movement coupled equation derived in this paper.