Depression is a common and serious mental disorder. About 1.9 million people in Taiwan are identified as having depression. There is a trend of increase of the prevalence of depression, three times more depressed persons within the past six years. A few patients with depression were in treatment. Therefore, an available algorithm will be build to measure the neurophysiology of depression. In this study, the physiological signals from depressed patients will be compared with those from normal people. This experiment use different pictures expresses happiness, sadness fear, and disgust to cause the emotion of subjects. The physiological signals of the patient is measured at the same time. The preliminary results show that the galvanic skin response, heart rate variability, and blood volume pulse of patients with depression is lower than the normal people does. More subjects will be evaluated in the project for investing the clinical significance.