Pelvic disruption is among the most complex injuries in orthopedic surgery because of the complex fracture patterns in the pelvic structure. Traditional preoperative planning using two-dimensional medical images usually encounters the problem of insufficient information for accurate assessment. In our previous work, a preoperative planning system that uses three-dimensional (3D) medical images and models was developed for the pre-surgical assessment, planning, and simulation of pelvic surgery. In this study, two additional functions, namely semi-automatic bone reduction and several types of fixation simulation are proposed to enhance the integrality of the proposed system for clinical applications. Ten clinical cases are presented for feasibility verification. For some of the cases, the surgeon carries out the simulation first, and then performs the surgery using procedures very similar to those in the simulation. The primary contribution of the proposed system is that the surgeon can go through the critical part of the surgery with the proposed 3D planning and simulation to fully understand the fracture pattern and make an appropriate surgical plan beforehand.