Abstract: The restorations of skull images are in great need of being solved in the craniofacial morphology research.Because there are clear contours in CT image，an approach of repairing is presented based on the geometry symmetry of the images.The method calculates the symmetry axis through optimal search strategy，analyzes the pros and cons of repair by filling directly and fitting，and repairs the hole in the skull by using least squares fitting.The numerical results prove that the algorithm in the paper discovers the symmetry axes of the CT images accurately，the restored image is received perfectly.