Abstract: In this paper, the combination of loop transfer recovery (LTR) observer and sliding mode control (SMC) is researched to deal with input time-delay system which has extern disturbance and parameter perturbation. The input time-delay system was rewritten into system without any time-delay by utilizing non-singular linear transformation. Then the SMC controller was designed based on the system without time-delay. Finally, an asymptotic stability of the system was given. Simulation results show that the designed controller has good performance and the steady-state of time-delay system, which has noise disturbance and parameter perturbation, could be reached quickly.