The package structure may includes: a sensor chip having a detecting device formed on a front surface of a substrate; through electrodes that are arranged at predetermined positions of the substrate around the detecting device, electrically insulated at circumferences thereof, pierce the substrate from the front surface to a rear surface, are connected with lead patterns of the detecting device on the front surface side, and connected with signal fetching means for the outside on the rear surface side; a flow path body on which the sensor chip is mounted and which has a flow path (a conduction path) for a fluid being formed on a surface facing the detecting device and sealing means.