New surgical techniques utilizing computer-aided engineering have been recently developed to improve the quality of surgery and reduce the risk to patients. This paper reports the surgical cases using rapid prototyping assisted orthopeadic fracture surgery (RPAOFS). RPAOFS utilizes the symmetric characteristics of the human body, and the potential for RE and RP in which the physical shape is manufactured repidly from the CT data. The physical shape before the injury was manufactured from the RP using the mirror transformed CAD data of the uninjured extents. Subsequently, pre-operative planning, such as the selection of the proper implant, preforming of the implant, selection of the fixation positions, and surgery are performed utilizing the physical shape. RPAOFS was applied to two cases such as a distal tibia communited fracture and a proximal tibia plateau fracture. The surgical results showed that RPAOFS is an effective surgical tools.