To improve convenience in a wearable electronic apparatus that measures biological information. An electronic apparatus includes a sensor mechanism, a main body, and a retaining mechanism. The sensor mechanism acquires biological information of a user. The main body supports the sensor mechanism in a movable manner in an upper/lower direction. The retaining mechanism changes the sensor mechanism and the users body between an unpress state and a press state by moving the sensor mechanism at the main body. With the electronic apparatus, a displacement of the sensor mechanism from the body is prevented and the maintenance of a contact condition is secured, an optical measurement becomes possible therefore, it is thereby possible to improve convenience for a user without adjusting a position, etc.