Pelvic injuries refer to the disruption of the inherent structural and mechanical integrity of the pelvic ring. Sacroiliac screw fixation technique is often applied for the treatment of posterior pelvic ring injury, which is prone to the iatrogenic injury. This study will compare the intraoperative and postoperative variables of patients underwent sacroiliac screw fixation with intraoperative CT and conventional imaging to evaluate the effect. Thirty-two patients with posterior pelvic ring injury treated by sacroiliac screw fixation from January 2019 to December 2020 were enrolled in this retrospective study. All patients were divided into two groups according to the different assistance of intraoperative imaging. Subsequently, the correlative data were compared and analysed statistically. Twelves cases were assigned to intraoperative CT group, and the remaining twenty cases were assigned to conventional group. There was no significant difference in duration of surgery, fracture healing time, time to ambulation, complications, and Matta radiological score. There was statistically significant difference (p < 0.05) in sacroiliac screws insertion time, length of incision, intraoperative blood loss, quality of screws position, and adjusted Majeed functional score, especially in the sexual intercourse part. With the assistance of intraoperative CT, a less misposition and functional impairment could be achieved, and a more satisfactory curative effect could be developed. Sacroiliac screws fixation with intraoperative CT is a more accurate and ideal method to treat posterior pelvic ring injuries.