1. A bone plate manufacturing method, comprising: acquiring an original 3D craniofacial image of a patient; using an image processing system to perform an image reconstruction of the original 3D craniofacial image to obtain a reconstructed 3D craniofacial image, wherein the image processing system comprises a plurality of mechanical data specifying mechanical parameters of various parts of a cranioface; comparing the original 3D craniofacial image with the reconstructed 3D craniofacial image via the image processing system, and defining an image difference therebetween as a defected portion; retrieving a portion of the plurality of mechanical data that corresponds to the defected portion, and defining a mechanical compensation area on the reconstructed 3D craniofacial image that compensates the portion of the plurality of mechanical data of the defected portion; designing a bone plate mold with a thickness based on a surface shape of the mechanical compensation area; and manufacturing a bone plate using the bone plate mold.