Information technology has been applied to health management. In our laboratory, we have developed and produced prototypes of new sensors, and attempted to monitor various health parameters noninvasively and unobtrusively. This paper reviews the results of our research related to sensor development. The contents include unobtrusive monitoring in the bed, bath and toilet, and smart house. Then wearable sensors used for photoplethysmography, inertia sensor, deep body temperature measurement, and oxygen uptake monitor are presented. Finally, the requirement of regulatory science is commented.