Abstract: In order to improve the reliability of liver surgery planning,three-dimensional reconstruction of liver is created based on the data set of abdominal CT images.Two types of virtual liver resection are presented in this paper,i.e.,atypical resection and anatomical resection.Atypical resection can be realized in three modes:plane resection,sphere resection,and curved surface resection.Cutting plane provides plane resection from any angle and the visualization of the structures on the cutting surface.Sphere model can be parameterized and transformed to resect the surrounded region.Closed curve can be drawn manually to define the resection region on the surface of the reconstructed liver model.Liver segments are marked according to the structure of the liver vessel,and anatomical resection is realized by removing the assigned segments.The results of clinical trials indicate that the virtual liver resections provide a reasonable and useful basis for preoperative planning,and improve the success rate of surgery.