BACKGROUND: Popliteal artery aneurysms (PAAs) are generally complicated by thrombosis and distal embolization, whereas rupture is rare. The aim of this study was to describe the clinical characteristics and outcome in a cohort of patients who had surgery for ruptured PAA (rPAA). METHODS: Operations for rPAA were identified from the Swedish Vascular Registry, Swedvasc, 1987-2012. Medical records and imaging were reviewed. Comparison was made with patients treated for PAA without rupture. RESULTS: Forty-five patients with rPAA were identified. The proportion with rupture among those operated on for PAA was 2·5 per cent. Patients with rPAA were 8 years older (77·7 versus 69·7 years; P < 0·001), had more lung and heart disease (P = 0·003 and P = 0·019 respectively), and a larger mean popliteal aneurysm diameter (63·7 versus 30·9 mm; P < 0·001) than patients with PAA treated for other indications. At time of surgery, 22 of 45 patients were already receiving anticoagulants, seven for concomitant deep venous thrombosis (DVT) in the affected leg. There was extensive swelling of the whole leg in 20 patients. In 27 patients, the initial diagnosis was DVT or a Baker's cyst. All patients underwent surgery, all but three by the open method. There were four amputations, all performed within 1 week of surgery. One year after surgery, 26 of the 45 patients were alive. Among these, the reconstructions were patent in 20 of 22 patients. CONCLUSION: The diagnosis of rPAA is difficult, and often delayed. The condition affects old patients, who often are on anticoagulation treatment and have large aneurysms. The immediate surgical results are acceptable, but the condition is associated with a high risk of death within the first year after surgery.