The present invention relates to a tooth model generation method for performing simulation in a dental procedure. More specifically, the present invention is a technique for generating a 3D tooth model by generating a 3D head image on the basis of head CT image data, applying a matching process using 3D landmarks to a 3D mouth surface model and a 3D head image, obtaining a 3D tooth crown model by extracting each tooth from the matched 3D mouth surface model, generating a 3D tooth volume model by extracting each tooth region by applying a technique for extracting a region of interest from the 3D head image, and then synchronizing the coordinate system of the 3D tooth crown model and 3D tooth volume model. That is to say, the present invention relates to a tooth model generation method for dental procedure simulation in which a 3D mouth surface model and a 3D head image on the basis of a 3D tooth crown model and a 3D tooth volume model are matched and thus the 3D tooth crown model and the 3D tooth volume model are in the matched state, and which, by synchronizing these two models to use the same coordinate system to make the two into one 3D tooth model, reflects in real time a change in the teeth and mouth structure due to orthodontic treatment. The present invention may: generate a new type of tooth model by taking only merits from a conventional tooth model which is generated on the basis of a precise stone model without diagnosis information such as roots of teeth, and from a conventional tooth model generation method in which an error occurs due to limited data using X-ray photography of a human body but diagnosis information is maintained provide a 3D tooth model which, by extracting a 3D tooth crown model by generating a 3D mouth surface model in which the precise crown part of all teeth can be extracted without additional costs or equipment in an easier way than a conventional way, and by comparatively simply generating a 3D tooth volume model which contains di
