A semiconductor pressure sensor is intended to achieve reduction in size and cost by decreasing the number of terminals and the number of pads. In the semiconductor pressure sensor, in a first mode in which correction data is input to a memory, a voltage input change-over switch and an input/output change-over switch are operated by an input signal from a switch change-over terminal in such a manner that a voltage input terminal and an input/output terminal are connected to a digital circuit, whereas in a second mode in which an electric signal corrected and amplified is output, the voltage input change-over switch is connected to a semiconductor sensor chip by means of an input signal from the switch change-over terminal, and the input/output terminal is connected to a correction and amplification circuit.