A failure detection apparatus (10) acquires, as target data, sensor data output in a past reference period by a sensor (31), such as a millimeter wave radar or LiDAR (Light Detection And Ranging), mounted on a moving body (100). The failure detection apparatus (10) determines whether detected data indicating a characteristic of a detected object indicated by normal data, which is sensor data output when the sensor (31) is normal, is included in the acquired detected data in the past reference period. In this way, the failure detection apparatus (10) determines whether a failure has occurred in the sensor (31).