Objective To evaluate the safety and accuracy of modified percutaneous retrograde intramedullary screwing into the superior pubic ramus or anterior acetabular column for pelvic and acetabular injury. Methods A retrospective analysis was conducted of the 23 patients with pelvic and acetabular injury who had been treated with modified percutaneous retrograde intramedullary screwing into the superior pubis ramus or anterior acetabular column from June 2015 to June 2017 in Luoyang Orthopaedic Hospital of Henan Province. They were 12 men and 11 women, aged from 22 to 88 years (mean, 53 years). The injury included 17 pelvic fractures, 4 acetabular fractures, and 2 acetabular plus pelvic fractures. The safety and accuracy of screwing were assessed by postoperative physical and imaging examinations. The number of fluoroscopy and operative time were documented for each retrograde intramedullary screwing into the pubic symphysis or acetabular anterior column. The quality of fracture reduction was evaluated by the Mata criteria postoperatively. The Majeed and the Harris scores were used to evaluate the functional recovery of the pelvis and acetabulum at the last follow-ups. Results A total of 31 intramedullary screws were placed in the 23 patients. For insertion of one screw, the operative time ranged from 15 to 50 min (average, 35 min) and the number of fluoroscopy from 32 to 55 times (average, 45 times). Postoperative physical examinations revealed no iatrogenic neurovascular lesion and uneventful healing of incisions in all the patients. Postoperative imaging examinations showed that 29 screws were located completely in the bone and 2 ones protruded the cortical bone of the pubic anterior border; all the screws did not protrude into the acetabulum or broke through the pubic symphysis or the pubic cortex. By the Matta criteria, the postoperative fracture reduction was rated as excellent in 17 cases, good in 5 and fair in one, giving an excellent to good rate of 95.7%. Of this series, 19 were followed up for 6 to 24 months (mean, 13 months). All the fractures healed after 3 months. The Majeed scores at the last follow-up for the 13 patients with pelvic fracture were excellent in 12 and good in one. The Harris scores at the last follow-up for the 6 patients with acetabular fracture (including the 2 with pelvic fracture) were excellent in 5 and fair in one. Conclusion The modified percutaneous retrograde intramedullary screwing into the superior pubic ramus or anterior acetabular column is safe, convenient and precise, effectively reducing radiation and operative time. Key words: Pelvis; Acetabulum; Fracture fixation, internal; Surgical procedures, minimal invasive; Surgical techniques