Purpose: This study aimed to investigate the mid- to long-term benefits of high tibial osteotomy in advanced age patients. Methods: This retrospective study was conducted in our hospital from January 2017 to January 2021 with data prospectively collected, 47 patients with knee osteoarthritis who over 65 years old were included, and a 1:1 propensity score (PS) of patients 0.05), while the younger group had lower VAS and WOMAC scores than the advanced age group at the end of follow-up (P 0.05). Conclusions: Compared with younger patients, advanced age patients have similar short-term benefits, but less long-term benefits. We recommend that patients proposed for HTO be discriminated by eFI, and patients with higher scores should be cautiously selected.