This paper proposes an adaptive non-singular fast terminal sliding mode control (NFTSMC) method to effectively enhance the speed control performance of induction motors under external disturbances and parameter variations. First, an adaptive nonlinear control method is designed to improve the system""s disturbance rejection capability and dynamic response performance while suppressing chattering in sliding mode control and planning the sliding mode convergence rate. Second, the proposed sliding mode load torque observer (SMLTO) ensures rapid and accurate tracking of the actual torque during load torque fluctuations, reducing speed fluctuations caused by sudden changes in load torque and improving control precision and robustness. Additionally, the proposed method employs a non-singular terminal sliding mode control approach, accelerating the system state convergence rate and avoiding the singularity issues in traditional sliding mode control. Experimental results show that the proposed method significantly improves the robustness and response speed of the induction motor speed control system and demonstrates excellent load torque observation performance.