A semiconductor pressure sensor having plural pressure sensitive diaphragms and capable of producing electric signals of at least two pressures.A semiconductor pressure sensor has a semiconductor single crystal chip (1) on which two diaphragms (12a, 12b) are shaped, pairs of strain gauges (13a and 14a, and 13b and 14b), each of which pairs are constructed on each pressure sensitive diaphragm, electrodes (15a and 16a, and 15b and 16b) which are provided for electrical connections of these strain gauges on the semiconductor single crystal, and an insulating substrate of borosilicate glass, the thermal expansion coefficient is substantially equal tol that of said semiconductor single-crystal chip, wherein the semiconductor single-crystal chip (1) and the glass substrate (2) are bonded to each other by an Anodic Bonding method, thereby being able to obtain a semiconductor pressure sensor which scarcely producing errors outputs.