1. A method for aligning three-dimensional shape data in a three-dimensional shape model generating system, said three-dimensional shape model generating system including a camera, a three-dimensional measurement device, and a processor, the method comprising the steps of: performing photogrammetry with said camera of an object having a multiplicity of target marks thereon to obtain a three-dimensional position and an average sight line vector of each of the target marks by a calculation; performing the three-dimensional measurement of the object with said three-dimensional measurement device to obtain a three-dimensional position and a normal vector for each of the target marks; determining, utilizing said processor, a correspondence between the three-dimensional position of each of the target marks obtained by the photogrammetry and the three-dimensional position of each of the target marks obtained by the three-dimensional measurement, by using the three-dimensional position and the average sight line vector of each of the target marks obtained by the photogrammetry and the three-dimensional position and the normal vector of each of the target marks obtained by the three-dimensional measurement; and aligning, utilizing said processor, the three-dimensional shape data obtained by the three-dimensional measurement based on the correspondence between the three-dimensional positions of the target marks.