Two types of skin incision, pararectal and transverse, in the retroperitoneal approach to aorto-iliac region were compared. For the last 3 years, 34 abdominal aortic aneurysms, excluding ruptured cases, and 43 cases of aorto-iliac occlusive disease were all operated on by a retroperitoneal approach in our hospital. Of these, 36 patients underwent pararectal incision (P group) and 41 patients transverse incision (T group). An Octopus^® retractor yielded a wide operative field in all cases. The mean interval from the start of the operation to the aortic cross clamp were almost equal in the two groups (89.7 and 91.1 minutes). The mean amount of intraoperative bleeding was significantly smaller in the T group (749ml) than in the P group (1, 096ml). The mean interval after surgery to beginning peroral alimentation, weaning from analgesics and discharge from the hospital were all significantly shorter in the T group (1.6, 3.3 and 10.8 days) than the P group (2.8, 4.8 and 15.8 days). Transverse incision for a retroperitoneal approach to the aorto-iliac region is preferable for an early recovery and short hospital stay.