We developed a computer-aided interactive surgical simulation system for craniofacial anomalies based on three-dimensional (3-D) surface reconstruction CT imaging. This system has four functions: 1) 3-D surface reconstruction display with an accelerated projection method; 2) Surgical simulation to cut, move, rotate, and reverse bone-blocks over the reference 3-D image on the CRT screen; 3) 3-D display of the simulated image in arbitrary views; and 4) Prediction of postoperative skin surface features displayed as 3-D images in arbitrary views. Retrospective surgical simulation has been performed on three patients who underwent the fronto-orbital advancement procedures for brachycephaly and two who underwent the reconstructive procedure for scaphocephaly. The predicted configurations of the cranium and skin surface were well simulated when compared to the postoperative images in 3-D arbitrary views. In practical use, this software might be used for an on-line system connected to a large scale general-purpose computer.