PROBLEM TO BE SOLVED: To provide an eating motion detector capable of accurately detecting presence/absence of an eating motion that is a motion of a user's carrying food to his/her mouth.SOLUTION: An eating motion detector comprises: an acceleration sensor 10 mounted to a chest or the upper part of a belly of a user； and a processing device 100 which determines that an eating motion of the user occurs when detecting a series of the user's motions of "pause, bending forward, pause, returning backward, and pause" on the basis of an output signal of the acceleration sensor. The processing device determines presence/absence of the eating motion of the user on the basis of a correlation coefficient between time series signals having a predetermined pattern corresponding to the series of the motions and a time series of output signals of the acceleration sensor.
