To provide a pressure sensor hardly damaged if an excess pressure is applied and easily assembled.

Both ends of a crystal oscillator 30 are bonded to the outer circumferential edge of a recess 23a in a diaphragm 23. A second spacer 22b, a first spacer 22a and a base body 21 are provided so as to surround the crystal oscillator 30 in the described order on the lower side of a surface of the diaphragm 23 on which the recess 23a is formed. The Young's modulus of an adhesive for bonding the first spacer 22a and the base body 21 is lower than that of the adhesive for bonding the diaphragm 23 and the second spacer 22b.