Background The outcome after veno-venous extracorporeal membrane oxygenation in elderly patients is supposed to be unsatisfactory. Our primary aim was to determine the influence of advanced age on short- and long-term outcomes; the secondary aim was to analyze risk factors for impaired outcomes. Methods Between January 2006 and June 2020, 755 patients received V-V ECMO support at our department. Patients were grouped according to age (18-49.9, 50-59.9, 60-69.9, >= 70 years old), and then retrospectively analyzed for short- and long-term outcomes. Risk factors for in-hospital mortality and death during follow-up were assessed using multivariate regression analysis. Results Duration of V-V ECMO support was comparable between all groups median (8-10 days, p = 0.256). Likewise, the weaning rate was comparable in all age groups 68.2%-76.5%; (p = 0.354), but in-hospital mortality was significantly climbing with increasing age (n = 91 vs. 50-59.9 years 37.1%/n = 73, vs. 60-69.9 years 45.6%/n = 78 vs. >= 70 years 51.8%/n = 44; p < 0.001). Older age groups also showed significantly reduced cerebral performance category scores. The multivariate logistic analysis yielded age, acute and chronic hemodialysis, bilirubin on day 1 of support, malignancy, and primary lung disease as relevant risk factors for in-hospital mortality. Age, coronary artery disease, presence of another primary lung disease, malignancy, and immunosuppression were risk factors for death during follow-up. Conclusion In V-V ECMO patients, advanced age is associated with more comorbidity, impaired short- and long-term outcome, and worse neurological outcome.