Taking the HVAC with time delay characteristics as the controlled object, the Smith predictive control algorithm and the adaptive algorithm are combined, and the adaptive law is derived based on Lyapunov's stability theory, and the Smith adaptive identifier is designed, so as to realize the self-tuning of controller parameters, and solve the problem of parameter time-varying in the control process, and the control effect is optimized. Experimental simulation results show that the Smith adaptive identifier control algorithm is better than the conventional Smith predictive control algorithm.