<p>The synchronization and load tracking control of multi-motor drive systems have complex nonlinear dynamic problems, including the unmeasurable states and the external disturbances. A novel synchronization and tracking control method for the multi-motor driving systems based on the states mean deviation coupling is proposed in this paper. The model of multi-motor driving system with the backlash and external disturbance is established. The state and disturbance observers are designed to estimate the unmeasurable states and total disturbances of the system to ensure the bounded convergence of the observation error. An improved dynamic surface tracking controller and a robust synchronization controller based on the states mean deviation coupling are designed. The tracking controller is combined the continuous hybrid differentiator with the dynamic surface control. The robust synchronization controller enable to avoid the coupling effect between synchronization and tracking. The experimental results show that the proposed control method can effectively improve the multi-motor synchronization and load tracking performance.</p>