[Purpose] Exercise therapy during dialysis is currently being recommended since it is easy for patients to follow and results in high participation rates. In this study, this therapy was performed for elderly patients undergoing maintenance dialysis, and its effects were examined. [Subjects and Methods] Seven elderly patients (age: 70.6 ± 4.4) with chronic renal failure, who were able to perform exercises during maintenance dialysis, received the exercise therapy 2 or 3 times weekly for 3 months. Lower-limb muscle strength as well as the standardized dialysis dose (Kt/V) was measured before and after intervention. The patients were also evaluated using the 30-sec chair stand test (CS-30), the World Health Organization QOL Assessment 26 (WHO-QOL26), and a questionnaire. [Results] The lower-limb muscle strength and circumference, CS-30 score, and Kt/V values improved after intervention, but the difference was not significant. Significant differences were observed only in the WHO-QOL26 score. [Conclusion] The outcome was particularly favorable in terms of the quality of life (QOL). Based on the results from the questionnaire, the higher QOL may be due to the patients’ development of a positive attitude toward these activities. Although there were no significant differences, the values for the other criteria also improved, thereby supporting the effectiveness of exercise therapy to maintain or improve the patients’ motor functions and activity daily living (ADL) ability.