A design method of inverted decoupling control, based on Smith predictive control, is proposed for TITO time-delay process which is common in industrial application. By analyzing the decoupled model, the Smith predictive controller is developed that adopting the concept of internal model control. According to the research on the control model as FOPDT, the method of developing the controller and analysis of robust stability is completed. The decoupling control scheme not only can absolutely decouple the responses of system outputs but also guarantee the nominal performance and robustness. The simulation outcomes verify the effectiveness and superiority of the proposed method.