1. An object type determination apparatus for determining a type of an object the image of which is picked up by an image pick-up means, comprising: an object area extracting means for extracting an area of an object from an image picked up by the image pick-up means; an object end point extracting means for extracting an end point of an image portion of the object from the area of the object extracted by the object area extracting means; an object periodicity determination means for calculating time series data of a feature value representing a size of the image portion of the object using the end point of the image portion of the object extracted by the object end point extracting means from the area of the object extracted by the object area extracting means for respective ones of time series images picked up by the image pick-up means, to determine whether the feature value changes with prescribed periodicity; and a living body determination means for determining the object having the feature value which is determined to change with periodicity by the object periodicity determination means as a living body.