Objective 　To investigate the safe range of intramedullary screw channel of superior pubic ramus fractures with the methods of digital anatomy.　Methods　A retrospective analysis was conducted with computed tomography (CT) images of pelvis from17 adult patients (34 cases of hemipelvis). We built virtual cylinder of intramedullary screw channel with Mimics according to the common types of superior pubic ramus fracture. With three-dimensional measurement tools, we measured the maximum width, depth, range of entry points and angles of the screw channels, determined the patterns of them and the scope of the security.　Results For medial 1/2 fractures, the virtual cylindrical was of an average of (9.64±0.79) mm in maximum diameter, (67.88±6.07) mm in length and sagittal screw angle ranged from (44.03±2.29)° to (50.41±3.33)°; in terms of the lateral 1/2 fracture, the maximum diameter of the virtual cylindrical was (11.25±1.45) mm, (96.82±6.76) mm in length, the angle between the screw and the sagittal plane ranged from (36.12±2.76)° to (43.38± 3.30)°. The differences between men and women were statistically significant, the data of different location of fractures between the two groups were statistically significant.　Conclusion　Digital anatomical studies of the safe range of intramedullary screw channel of superior pubic ramus fractures increase the safety and accuracy of the intramedullary screws fixation.