A piezoelectric sensor (10) having an elongated-sheet shape includes a piezoelectric layer (11) containing an elastomer and piezoelectric particles and electrode layers (12a and 12b) which are disposed with the piezoelectric layer (11) sandwiched between the electrode layers. In the piezoelectric sensor (10), a pressure sensing region (S) has a length of 500 mm or longer in a longitudinal direction thereof； the electrode layers (12a and 12b) contain an elastomer and flaky conductive materials and are capable of elongating by 10% or more in one direction of plane directions； and when a space between one end portion (A) and the other end portion (B) of the pressure sensing region (S) in the longitudinal direction is set as a measurement zone, an electrical resistance in the measurement zone in the electrode layers (12a and 12b) is 3,000Ω or lower, and the specific Expression (I) is satisfied.
