Background Very elderly patients represent a distinct patient group in clinical setting in terms of a decision for trans-catheter aortic valve replacement (TAVR) when one considers the potential improvement in the quality of life (QoL) on one hand and the benefit to risk ratio on the other. This study aimed to compare functional and QoL outcomes of TAVR between octogenarians and septuagenarians. Methods This prospective cohort study included 136 elderly patients (70 to 89 years of age), who underwent transfemoral TAVR due to degenerative aortic stenosis. Patients were allocated into one of the following age groups: septuagenarians (n = 67) and octogenarians (n = 69). Preoperative and early postoperative clinical parameters were recorded. In addition, QoL of the patients was evaluated using SF-36 questionnaire preoperatively and six month postoperatively. Results Groups were similar in terms of early postoperative mortality and morbidity parameters. The mean New York Heart Association (NYHA) class improved after TAVR in both groups. In addition, all SF-36 norm-based scale and SF-36 summary scale scores improved significantly in both groups during the postoperative period. Postoperatively, physical functioning, general health and physical component summary scores were significantly better in the septuagenarian group (P = 0.02, 0.01, 0.03, respectively). Conclusion Although the improvement in the QoL in terms of physical health was more marked in septuagenarians than in octogenarians, substantial benefits on the QoL and particularly on mental health seem to justify re-consideration of TAVR indications in the very elderly.