An abnormality determination system includes: an autonomous moving object including at least one distance measuring unit that is disposed to face a road surface in a moving direction ant that measures a distance to the road surface; a charging unit including a connection terminal for charging a battery of the autonomous moving object; a stepped portion disposed on a road surface which is subjected to measurement by the distance measuring unit when the autonomous moving object is connected to the connection terminal of the charging unit and is positioned; and a determination unit configured to determine whether the distance to the stepped portion measured by the distance measuring unit at the time of positioning is less than a threshold value.