The objective of this study was to evaluate the outcomes of open and endovascular repair of popliteal artery aneurysms (PAAs) on the basis of the initial diameter of the aneurysm in a retrospective single-center experience. From January 2000 to June 2016, there were 221 consecutive open and endovascular interventions for PAA repair performed. Data concerning these interventions were prospectively inserted in a dedicated database. A retrospective analysis of the database was performed, and 105 interventions performed for PAAs with a <30-mm maximum diameter were found (group 1); in 71 cases, the diameter was between 30 and 39 mm (group 2); and in the remaining 45 cases, it was >39 mm (group 3). The three groups were compared in terms of clinical, anatomic, and surgical characteristics and of perioperative (<30 days) outcomes with two tests; follow-up results were compared with Kaplan-Meier curves and log-rank test. There were no differences between the three groups in terms of demographics, risk factors, and comorbidities. PAAs were symptomatic in 54 cases in group 1 (51%), in 28 cases in group 2 (40%), and in 25 cases in group 3 (55%; P = .1). Twenty-five patients in group 1 (24%), 23 patients in group 2 (33%), and 14 patients in group 3 (31%; P = .3) underwent endovascular exclusion of their PAAs; in the remaining cases, an open surgical intervention was performed. There were no differences between the two groups in terms of perioperative deaths, thromboses, and amputations. Follow-up was available in 214 patients (97%), with a median duration of 30 months (range, 1-192 months). There were no differences between the three groups in terms of estimated 5-year survival. Primary patency rates at 5 years were 69% in group 1, 57% in group 2, and 47% in group 3 (P = .09; log-rank, 3.3); the corresponding figures in terms of secondary patency were 74%, 76.5%, and 48% (P = .03; log-rank, 6.9). Limb preservation rate at 5 years was similar between the three groups (90%, 95%, and 90%, respectively; P = .9; log-rank, 0.1). Similar results on the same outcomes were found on separate analysis of symptomatic and asymptomatic lesions. In our experience, open and endovascular management of PAAs provided poorer patency rates in patients treated for large aneurysms than in patients treated for smaller lesions. An aggressive policy of early repair of PAAs before enlargement occurs seems be justified.