To provide a pressure sensor which has high accuracy, high reliability, and especially high moisture resistance without pressure sensitivity changing according to the change in environmental conditions.

A pressure sensor 10 includes: a pressure sensitive element 40; a supporting member 30 to which the pressure sensitive element 40 is fixed; and bellows each of which has an opening part and a closing part on each end. The closing parts are bonded to the supporting member 30 by using an adhesive bond 70. The supporting member 30 has recesses into which the closing parts can be inserted at contact parts with the bellows.