DMC-PID cascade control strategy was adopted to apply on high accuracy constant temperature air conditioning system because constant temperature room had large inertia, delaying, a few interference factors characteristics. The construction type of DMC-PID cascade control system was designed and the prediction model of inner loop and outer loop was determined, and then MATLAB software was applied to simulate and compare robust stability, tracking performance, anti-jamming capability characteristics of DMC-PID cascade control algorithms with other algorithms. Through studies, the overshoot of DMC-PID cascade control of room temperature reduced 2% in comparison with the PID algorithm, but was much larger than that of DMC algorithm. Its regulation time was nearly the same to that DMC algorithm, but cut down 25% in comparison with the PID algorithm. At last, the simulation result showed DMC-PID cascade control strategy application on temperature control of high accuracy constant temperature room had feasibility and effectiveness, and the control strategy had strong robust stability, tracking performance, anti- disturbance ability characteristics.