A disparity value deriving device for deriving a disparity value representing disparity for an object from a reference image (Ia) obtained by a first imaging unit capturing an image of the object and a comparison image obtained by a second imaging unit capturing another image of the object, the disparity value deriving device comprising: an acquisition unit configured to calculate respective degrees of matching of a plurality of candidate regions each serving as candidates for a corresponding region in the comparison image (Ib) corresponding to a first reference region in the reference image (Ia), based on a luminance value of the first reference region and luminance values of the candidate regions specified by shifting positions by shift amounts (d) obtained by partially removing predetermined shift amounts from a predetermined shift range, from a region corresponding to a position of the first reference region, on the epipolar line in the comparison image (Ib) based on the first reference region; a synthesizer configured to calculate a synthesized degree of matching of each of the candidate regions by aggregating the degree of matching in the comparison image (Ib) for a second reference region in a neighborhood of the first reference region, with the degree of matching of the candidate region, based on the shift amounts (d) by which the positions are shifted; and a deriving unit configured to derive the disparity value, based on the shift amount (d) corresponding to a minimum value or a maximum value of the synthesized degrees of matching (Ls) of the respective candidate regions in the comparison image (Ib), characterized in that when the shift amounts by which the positions are shifted are arranged in ascending order, the features are configured such that a difference in value between adjacent shift amounts increases as values of the shift amounts increase, wherein a difference in value between adjacent shift amounts is two or more pixels. an acquisition unit configured to calculate respective degrees of matching of a plurality of candidate regions each serving as candidates for a corresponding region in the comparison image (Ib) corresponding to a first reference region in the reference image (Ia), based on a luminance value of the first reference region and luminance values of the candidate regions specified by shifting positions by shift amounts (d) obtained by partially removing predetermined shift amounts from a predetermined shift range, from a region corresponding to a position of the first reference region, on the epipolar line in the comparison image (Ib) based on the first reference region; a synthesizer configured to calculate a synthesized degree of matching of each of the candidate regions by aggregating the degree of matching in the comparison image (Ib) for a second reference region in a neighborhood of the first reference region, with the degree of matching of the candidate region, based on the shift amounts (d) by which the positions are shifted; and a deriving unit configured to derive the disparity value, based on the shift amount (d) corresponding to a minimum value or a maximum value of the synthesized degrees of matching (Ls) of the respective candidate regions in the comparison image (Ib), characterized in that when the shift amounts by which the positions are shifted are arranged in ascending order, the features are configured such that a difference in value between adjacent shift amounts increases as values of the shift amounts increase, wherein a difference in value between adjacent shift amounts is two or more pixels.