A three-dimensional geometry measurement apparatus including: a preliminary measurement part that creates a plurality of pieces of preliminary measurement data indicating three-dimensional coordinates of a reference point on a reference instrument; a reference data creation part that creates reference data; a calculation part that calculates a correction value on the basis of the reference data and the preliminary measurement data which does not match the reference data; a target measuring part that creates target measurement data indicating results of measuring a measurement point of the object to be measured; a correction part that corrects the target measurement data in the measurement system corresponding to the preliminary measurement data that does not match the reference data, on the basis of the correction value; and a geometry identification part that identifies a geometry of the object to be measured using the corrected target measurement data.