The present invention provides a moving object detection device that includes: a spatiotemporal data generation unit 120 which generates time series data which arranges data indicating a moving object along a temporal axis, based on an output from a camera 100; an inter-leg information unit 140 which extracts, based on the generated time series data, inter-leg information, which is information regarding a temporal change in an inter-leg area arising from movement of a moving object that has two or more legs; a periodicity analysis unit 150 which analyzes a periodicity within the extracted inter-leg information; and a moving object detection unit 160 which generates, from the analyzed periodicity, movement information that includes the presence or lack thereof of a moving object.