A pressure sensor ( 1 ) comprises a pressure-sensitive element, formed by a die made of semiconductor material (6), particularly silicon, a substrate (2) and an electric circuit (7) to which the die (6) is electrically connected. A face of the die (6) is directly bonded to a flat face (5) of the substrate (2) through at least one layer of glassy material (10). Preferably the electric circuit comprises a plurality of electrically conductive tracks (7), at least part of which is formed on the flat surface (5) of the substrate (2).