A bone plate manufacturing method includes an image acquisition step, an image reconstruction step, a comparison step, a data retrieval step, a model designing step and a bone plate manufacturing step. The image acquisition step acquires an original 3D craniofacial image. The image reconstruction step uses an image processing system to perform image reconstruction of the original 3D craniofacial image to obtain a reconstructed 3D craniofacial image, and the image processing system comprises a plurality of mechanical data. The comparison step compares the original 3D craniofacial image with the reconstructed 3D craniofacial image and defines the image difference therebetween as a defected portion. The data retrieval step retrieves a portion of the mechanical data and defines a mechanical compensation area on the reconstructed 3D craniofacial image. The model designing step designs a bone plate mold. The bone plate manufacturing step manufactures a bone plate.