The virtual surgical system is a surgical simulated software adopting image processing and 3-D visualization technology. It can help the surgeons to determine the operating position, simulate operation and plan for a optimal operation. VTK which exhibits high performance in visualization and ITK which has strong ability in image processing were integrated to solve the key problems such as image segmentation, image registration and fusion, 3-D reconstructing and virtual cropping. Experiments indicated that the integrated 3-D virtual surgical system can help surgeons to observe the surgical process and improve its reliability and quality.