This study was conducted to compare the early and mid-term results of the medial and posterior approaches in the surgical treatment of popliteal artery aneurysms (PAAs). From 1992 to 2006 in three hospitals, 110 popliteal aneurysms needed surgical repair by a posterior or a medial approach. Of 36 aneurysms repaired by the posterior approach, 33 could be case-matched to a medially excluded PAA according to the criteria of (1) patient age, (2) cardiovascular comorbidity, (3) indication for PAA repair, (4) diameter of PAA at time of surgical repair, (5) number of distal outflow vessels at time of surgical repair, and (6) type of bypass or interposition graft (venous or polytetrafluoroethylene). During the 30-day postoperative period, seven complications (21%) occurred in each group, no patients died, and no amputations were necessary. Two patients in the posterior group vs none in the medial group (P < .05) needed thrombectomy because of occlusion of the reconstruction. The mean follow-up was 47 months (range, 2 to 176). In this period, 13 deaths occurred, but none were related to the previous interventions. The primary patency rates at 6 months and at 1, 3, and 4 years were 84%, 79%, 66%, and 66% in the posterior group and 96% (P < .05), 93% (P < .05), 76% (P = NS), and 69 % (P = NS) for the medial group, respectively. The secondary patency rates at 6 months, and at 1, 3, and 4 years were 100%, 100%, 100%, and 90% in the posterior group and 96%, 96%, 96%, and 90% in the medial group, respectively (P = NS). Limb salvage rates were 97% for the posterior group and 100% for the medial group (P = NS). No neurologic complications or venous damage was seen in either group. Irrespective of approach, venous reconstructions resulted in significantly higher patency rates compared with prosthetic reconstructions at the 3-year follow-up (84% vs 67%, P < .01). During follow-up, which included duplex scanning, two patients in the medial group needed renewed surgical intervention and posterior exclusion because of persistent flow and growth of the native aneurysm. Early (<1 year) primary patency rates of the medial approach were significantly better than the posterior approach, possibly because of the limited posterior exposure. However, in the absence of a significant difference in long-term primary and secondary patency rates between the posterior and medial approach, and considering the substantial risk of aneurysm growth after medial approach (up to 22%), the posterior approach might be the surgical method of preference for PAA repair in the long run.