Blood pressure and pulse have important role on health, particularly on medical field. There are two kinds of blood pressure disorder: hypertension and hypotension. Hypertension often becomes the most common non-communicable disease in many countries. Blood pressure monitor is a kind of equipment used to measure the blood pressure. For a long time, mercury blood pressure monitor is commonly used by people. However, these days, the use of this monitor is restricted because of environmental problem. Therefore, the writer designs a digital blood pressure monitor which has blood pressure indicator. The module is digital and portable. The use of digital blood pressure monitor is considered to be more practical and easy. The test was done by comparing the module and sphygmomanometer aneroid which has been calibrated. The measurement of the blood pressure is done on point 40, 60, 80, 100, 120, 140 and 160 mmHg. The result is that there is a maximal error for about 5.5%. The weakness of the sensor becomes the great influence on the resulted error.