This paper proposes a two-stage identification method for the dual-motor servo system with nonlinear dead-zone and backlash.For the situation that the motor inertia, the equivalent viscous friction coefficient and the size of the backlash are unknown, the Legendre polynomial is utilized to segment the backlash model of dual-motor servo system.The parameters of the dual-motor servo system are identified by using the least square method(LSM). Finally, a simulation experiment is carried out to verify the effectiveness of the proposed two-stage identification method, and the proposed method can accurately identify the motor parameters and backlash parameters.