Human blood glucose metabolism is viewed by biomedical engineers as a slow nonlinear system whose structure and parameters are not known exactly. A significant time delay is usually involved in the measurement process of glucose concentration. This paper introduces the real-time digital control of such a process. A three term microcontroller is employed in real-time processing of the glucoregulatory system. The coefficients of this controller are optimized using a recently developed criterion to place the closed-loop poles at desired locations. The simulation results show that the input waveform is relatively steady during the control process, and the microcontroller employed is practicable as well as providing satisfactory in vivo blood glucose regulation.