Provided is an object detection device including: a detection unit configured to detect objects for every detection period to output detection information containing a reliability for each of the detected objects; a determination unit configured to: increment a detection count for each of the objects; calculate, for each of the objects, a sum of latest N reliabilities in the detection period; and determine, as a normally recognized object, an object for which the sum is equal to or larger than a first threshold value, which is set in advance depending on the detection count; and a control unit configured to output, as normally detected object information, detection information on the normally recognized object.