Objectives　To provide applied anatomic data for preventing the injury of the important structures in the ilioinguinal approach of surgical treatment forpelvic fracture. Methods the anterior superior iliac spine, the pubic tubercle and the inguinal ligament were chosen as the mark point for observing and measuring  morphologic features of lateral femoral cutaneous nerve, ilioinguinal nerve, pectineus branch of the femoral nerve and obturator artery in 15 adult cadaveric specimens (30 sides, 9 male, 6 female). The data were analyzed statistically.　Results　①LFCN traveled medial to anterior superior iliac spine through the inguinal ligament could be observed  in 29 sides (96.67%), (20.01 ± 0.32)mm; LFCN was surrounded by the fibers of the inguinal ligament could be observed in 10 sides(33.33%); LFCN was covered by a fascial sheath formed by the deep fascia could be observed 14 sides (46.67%). ② The distance between the point of ilioinguinal nerve passed through the obliquus internus abdominis and the center of the anterior superior iliac spine was (5.41± 0.50) mm, The distance between the point of ilioinguinal nerve penetrated from the aponeurosis of oblique externus abdominis and the center point of pubic tubercle was (18.04 ± 0.21) mm.　Conclusion　The LFCN must be protected in the exposure of the medial side of the iliac wing and sacroiliac joint by preventive release of the tensor fascia and the inguinal ligament . To prevent the injury to ilioinguinal nerve, incision of the aponeurosis of the oblique externus abdominis should be performed at 5cm superior to medial and lateral ends of the inguinal ligaments. Identification and ligation of the obturator vessels to ramus of pubis should be carried out prior to exposure of iliopectineal eminence  so that uncontrollable bleeding can be avoided