In a pressure sensor, a cap-shaped shielding member (17) to block an electric field undesirable for a signal processing electronic circuit unit of a sensor chip (16) is supported by an end surface of a disk conductive plate (19) between one end surface of the sensor chip (16) in a liquid sealing chamber (13) and a diaphragm (32). The conductive plate (19) is electrically connected via a group of input-output terminals (40ai) and bonding wires (Wi), for example, and the sensor chip (16) is supported by one end portion of a chip mounting member (18) which is electrically connected via the group of input and output terminals (40ai) and the bonding wires (Wi).