A blood glucose level decreasing system that decreases blood glucose level of a patient by blocking the sympathetic innervation to liver and pancreas and smooth muscles of the arteries reaching to liver and pancreas with noninvasive electrostimulation of the skin which have the sympathetic nerves originating from the same spinal cord segments. The blood glucose level decreasing system has at least one sensor for measuring the blood glucose level of the patient; at least two electrodes that are placed to skin dermatomal of the patient; at least one stimulator that sends electrical signals to the electrodes to block the sympathetic nerve innervation to smooth muscles of hepatic artery proper and liver, and expand liver artery of the patient; and at least one control unit, which receives the blood glucose level from the sensor, compares received level with a predetermined threshold value and controls the stimulator according to the result.