A method for manufacturing an electronic apparatus functioning as a component of a wireless communication system includes providing a lower part formed with a first concave portion, a second concave portion spaced away from the first concave portion, and a third concave portion which couples the first concave portion and the second concave portion, providing an upper part for sealing the first concave portion, the second concave portion, and the third concave portion formed in the lower part, providing a module unit including a sensor which detects a physical quantity, and a radio communication unit which transmits data based on an output signal from the sensor, providing a battery for supplying power to the module unit, coupling the module unit and the battery by a wiring, and after the coupling the module unit and the battery, arranging the module unit in the first concave portion of the lower part.