The Rapid Prototyping (RP) manufacture technology, computer tomography (CT) image processing, and mechanical analyses were adopted to repair a skull defect injury. After the patient was inspected by spiral CT the data was exported to Digital Imaging and Communications in Medicine (DICOM) format. The data was processed with Mimics software to eliminate noise and gray-level registration. The processing filtered out the parenchyma data and preserved the bone data. The STL files were analyzed and processed by the Magics and put into the RP equipment. The RP equipment is one type of Stereo Lithography Apparatus (SLA) with laser light spot diameter that is 50.2 mm. The 3D models were analyzed to comply with the patients' requirements. The stereo lithography model emulated the mechanical properties and shape with the patient's bone. The titanium-alloy plate matched the anatomy well. The 3D reconstructed freeform model was accurate to within 0.2 mm.