Purpose : The purpose of this study was to determine the effects of upper extremity volume, pain, and range of motion after participation in thera-band exercises according to the hand grip type in patients with breast cancer with upper extremity edema. We also aimed to determine the most efficient type of grip. Methods : The subjects were 10 female patients diagnosed with stage 2 breast cancer who had stage 2 lymphedema. Randomly, 5 patients each were allocated to the experimental and control groups. For six weeks, the patients in both the experimental and control groups exercised daily. In both groups, manual lymph drainage was applied for 1 hour. Afterward, patients in the experimental group placed their hands in the thera-band ring and exercised with their fingers outstretched. Patients in the control group exercised while holding the thera-band ring with a finger. Both the experimental group and the control group underwent measurements of the circumference of the upper extremity, pain, and range of motion of the shoulder joint at weeks 1, 2, 4, and 6 before and after exercise. Results : The upper arm circumference decreased by more in the experimental group in all weeks than before than that in the control group, and there was a statistically significant difference at 6 weeks. Compared with the difference between pre-exercise and 6 weeks post-exercise, the change in pain significantly decreased in the experimental group and showed a statistically significant difference. The shoulder range of motion increased in extension, external rotation, and internal rotation compared with that in the control group, and there was a statistically significant difference. Although the operating range increased in flexion and abduction, there were no statistically significant differences. Conclusion : In this study, we found that thera-band exercises with an open-hand grip are more efficient than thera-band exercises with a closed-hand grip in edema reduction, pain, and range of motion. In addition, it was found that it was more effective to continue the thera-band exercises with open-hand grip extended for at least 6 weeks rather than for a short time.