This study aimed to assess the efficacy of combined administration of dipeptidyl peptide-4 (DPP4) and sodium-glucose cotransporter-2 (SGLT2) inhibitors on metabolic disorders and their preferable and complementary effects. The effectiveness of a 24-week intervention on metabolic parameters (including glucose profile), physical functions (grip strength and calf circumference), and health-related quality of life (HR-QOL) was analyzed using the International Physical Activity Questionnaire and Geriatric Depression Scale 5. A total of 39 patients with type-2 diabetes mellitus (T2DM) treated with the combination of DPP4 and SGLT2 inhibitors were included in this multicenter pilot study. Combination therapy significantly reduced the HbA1c level (median [interquartile range]) after 24 weeks (pretreatment: 7.7% [7.3-8.2] vs. posttreatment: 7.1% [6.6-7.9], P < 0.001). The grip strength significantly increased after 24 weeks (1.7 ± 2.7 kg, P < 0.001), while the mean calf circumference and body mass index significantly decreased. In particular, administration of the SGLT2 inhibitor significantly increased total physical activity in participants aged ≥65 years (P = 0.003), while psychological QOL did not significantly improve. Combination therapy with DPP4 and SGLT2 inhibitors decreased HbA1c levels and improved physical function in patients with T2DM. This study confirmed the effectiveness of combination therapy for metabolic disorders and suggested its beneficial and complementary effects. Therefore, advances in treatment plans to achieve further improvements in glucose profiles using DPP4 and SGLT2 inhibitors are recommended to enhance the QOL of patients with T2DM. Clinical trial number: University Hospital Medical Information Network Center: UMIN000045375.