A three-dimensional measurement apparatus generates patterns to be projected onto the measurement object, images the measurement object using an imaging unit after projecting a plurality of types of generated patterns onto the measurement object using a projection unit, and computes the coordinate values of patterns on a captured image acquired by the imaging unit, based on the projected patterns, a geometric model of the measurement object, and information indicating the coarse position and orientation of the measurement object. Captured patterns on the captured image are corresponded with the patterns projected by the projection unit using the computed coordinate values, and the distances between the imaging unit and the patterns projected onto the measurement object are derived. The position and orientation of the measurement object are estimated using the derived distances and the geometric model of the measurement object, and the information on the coarse position and orientation is updated.