The present study aimed to determine the effectiveness of locomotion training on physical function and quality of life in patients with rheumatoid arthritis (RA) and identify factors associated with its effectiveness. [Participants and Methods] Data were obtained from 103 patients with rheumatoid arthritis who underwent locomotion training for 6 months using the Health Assessment Questionnaire Disability Index, pain visual analog scale, 10-meter walking speed, timed up-and-go test, single-leg standing time, grip strength, 25-question Geriatric Locomotive Function Scale, Short Form-8, fat-free mass index, and fat mass index. [Results] A significant improvement in the Health Assessment Questionnaire Disability Index, pain visual analog scale score, maximum 10-meter walking speed, timed up-and-go test, single-leg standing time, grip strength, and physical component summary in Short Form-8 was observed at six months. [Conclusion] The current study demonstrated that locomotion training for 6 months improved physical function, certain aspects of quality of life, and sarcopenia in patients with RA. We believe that locomotion training should be recommended as a non-pharmacological therapeutic option for improving physical function in patients with RA.