[Objective] For a dual-motor servo system with external disturbance torques, a terminal sliding mode control (TSMC) strategy based on a finite-time disturbance observer is proposed. The aim is to enhance the dynamic response quality, robustness, and cooperative motion accuracy between the dual motors under complex working conditions. [Methods] Firstly, a finite-time disturbance observer was designed to quickly and accurately estimate external disturbances, ensuring that the observation error converged in finite time. Second, a nonsingular terminal sliding mode surface was constructed to avoid singularity issues and enhance the system’s anti-interference capability. Then, synchronous feedback and an optimized reaching law were introduced to suppress chattering and ensure high-precision synchronization of the dual motors. Finally, based on the Matlab/Simulink simulations platfrom, the performance of the proposed TSMC strategy was compared and analyzed with that of the integral sliding mode control strategy. [Results] The results demonstrated that the proposed TSMC strategy exhibited significant advantages in system load tracking performance, trajectory tracking error, and dual-motor synchronization error. [Conclusion] The proposed TSMC strategy theoretically guarantees finite-time stability of the system and demonstrates significant practical advantages, including strong anti-interference capability, fast dynamic response, and high-precision synchronization. This achievement provides an effective solution for controlling high-performance dual-motor servo systems in scenarios with complex disturbances and stringent accuracy requirements.