We have been developing a monitoring system to measure human information from human body. In the previous study, we developed a digital integrated circuit that enables acquisition of heart rate from ECG (Electrocardiogram) instead of MPU (Micro Processing Unit). This circuit reduced the power consumption of the MPU from 97 μW to 19.7 μW. In this research, we redesigned an MPU specialized for the human monitoring system to aim at further lowering power consumption and verified it with a test model. The designed MPU has fewer logic elements than the commercially available MPU and consumes 383 nW power consumption when using standard cell with low power consumption. This can be 98.0% lower than the conventional MPU.