The permanent magnet external rotor hoist has subverted the traditional driving mode, enhanced the energy efficiency ratio, and facilitated the green, efficient, and energy-saving development of mining hoisting equipment. To enhance the speed control performance and robustness against load disturbance variations of the permanent magnet external rotor hoist, a composite sliding mode control method combining an improved disturbance compensation-based sliding mode controller and a sinusoidal switching sliding mode disturbance observer was proposed. The load changes were observed in real time, and the observed values were integrated into the control, improving the dynamic response capability during sudden load changes. Subsequently, a multibody dynamics load model of the permanent magnet external rotor hoist was established using Simulation X for joint simulation, and the dynamic characteristics of the permanent magnet external rotor hoist under multiple working conditions were investigated. The joint simulation results indicate that the load observer can accurately observe load changes and compensate for the disturbance values. The designed composite sliding mode control system exhibits superior dynamic performance compared to the traditional sliding mode control. The permanent magnet external rotor hoist based on the composite sliding mode control strategy can fulfill the requirements of stable heavy-load operation under diverse working conditions.