A piezoelectric film sensor (3) of a swallowing sensor (1) includes a plurality of sensing portions (3A) and (3B) in a longitudinal direction of the neck region. The piezoelectric film sensor (3) is located within a range of movement of thyroid cartilage (103), which occurs along with swallowing, and is attached to skin of an anterior neck region (102). The piezoelectric film sensor (3) individually outputs analog signals (S1a) and (S2a) along with deformation of the plurality of sensing portions (3A) and (3B). The swallowing sensor (1) includes pre-processing units (21) and (22) and a signal processing unit (23). Each of the pre-processing units (21) and (22) separates the analog signal (S1a) or (S2a) into a displacement signal that is a low frequency component and a sound signal that is a high frequency component. The signal processing unit (23) determines whether the swallowing occurs based on the displacement signal.