A
surface wave sensor device where an undesired
short circuit or deterioration in
measurement precision due to liquid adhesion is less likely to occur and that provides highly reliable measurement results. A surface sensor device (1), where elastic
surface wave elements (11, 21) are bonded, with thermo-compressive bonding anisotropic conductive sheets (7, 8) in between, on the first major surface (2a) side of a base substrate (2) having first through-hole conductors (5a, 5b, 6a, 6b), electrodes such as IDTs (13, 14) are formed on the first major surface (12a, 22a) side of piezoelectric substrates (12, 22) of the elastic
surface wave elements (11, 21), the electrodes being led out to the second major surface (12b, 22) side through second through-hole conductors (16a, 16b, 26a, 26b) arranged in the piezoelectric substrates (12, 22), and the first through-hole conductors (5a, 5b, 5e, 5f) are arranged superposed on the second through-hole conductors (16a, 16b, 26a, 26b) with the thermo-compressive bonding anisotropic conductive sheets (7, 8) in between.