To provide a three-dimensional information processor for easily measure even an object in a distance.

This three-dimensional information processor acquires three- dimensional information of an object to be image-picked up based on a principle of a triangulation by using image information at a plurality of viewpoints with images picked up on an imaging surface of an imaging device formed on a single chip. Similarity of the image characteristic of an image area exceeding a parallax zero point in the direction from a maximum parallax search point toward the parallax zero point in a search range on a predetermined epi-polar line is examined in addition to similarity of image characteristic of an image area at a plurality of predetermined search positions on a predetermined epi- polar line in other images than a reference image.