An image processing apparatus includes: a model pattern storage unit that stores a model pattern composed of a plurality of model feature points; an image data acquisition unit that acquires a plurality of images obtained through capturing an object to be detected; an object detection unit that detects the object to be detected from the images using the model pattern; a model pattern transformation unit that transforms a position and posture such that the model pattern is superimposed on an image of the object to be detected; a corresponding point acquisition unit that acquires a corresponding point on image data corresponding to each of the model feature points; a corresponding point set selection unit that selects a set of corresponding points on the plurality of images; and a three-dimensional position calculation unit that calculates a three-dimensional position of the image of the object to be detected.