A pressure sensor device (1) comprises: a pressure sensor (9) having a sensor body (9a) defined in which is a cavity (11) with a bottom surface (11a) belonging to a membrane portion (9′) of the body itself, a detection element operatively being associated to the membrane portion (9′), a connection structure (2) having a duct (2a, 15, 19) in communication with the abovementioned cavity (11), designed to receive a fluid a pressure of which is to be detected. The connection structure comprises a body (2) for supporting the pressure sensor (9), defining at least one respective passage (2a), and one compressible element (12) designed to be in contact with the fluid and configured to compensate possible volume variations thereof, the compressible element (12) being positioned at least partially within the cavity (11), in such a manner to substantially divide it into two opposite regions. The device (1) is provided with connection passages (12f) for maintaining different regions of the cavity (11) in fluid communication, i.e. equilibrate in pressure.