Currently,the internal fixation methods for unstable sacral fractures mainly include posterior tension band screw plate fixation,sacroiliac screw fixation,lumbopelvic fixation and triangular osteosynthesis.The purpose of the above internal fixation is to correct the deformity of the pelvic ring and lumbosacral joint and rebuild its stability,but incorrect selection will increase the risk of loosening or breakage of the internal fixation.However,there are no clear guidelines on how to select appropriate internal fixation according to different fracture types.To this end,the author discussed the selection of internal fixation method,the technique of screw placement,the new auxiliary instrumentation technology as well as internal fixation related infection so as to provide reference for the treatment of unstable sacral fractures.