In this paper, in order to get better robustness not only good response characteristics, we applied the Internal Model Control (IMC) to the system which includes time delay, and by using the Integral Square Error (ISE) and the complementary sensitivity function as the response and robustness measures respectively, to design the IMC controller. Here we first applied IMC and PID Control to the distributed constant system, and compared the results on response performance and robustness. Finally, for comparing the control results among the IMC, PT control and Smith predictor about response characteristics and robustness, we did the control experiments on the heat exchanger which includes time delay. Consequently, the response performance and robustness of the control system by using IMC are better than that of by using PI control and Smith predictor.