Purpose: The purpose of this study was to determine the effects of water exercise program on physical fitness, pain and quality of life(QoL) in patients with osteoarthritis. Methods: Thirty-four old women were divided into the exercise(EG, n=18) and control groups(CG, n=16) after 6-week self-help education program. The EG carried out 6-week supervised water exercise program(60min/day, 2days/wk). Physical fitness, pain, and QoL were assessed by Senior Fitness Test Manual(Rikli & Jones, 2005), Pain rating scale(0-10) and World Health Organization QoL BREF(Min et al., 2000), respectively. Results: Both EG and CG increased upper and lower-body strength(all, p<.05), which were measured by arm curl and chair stand, respectively. For flexibility test, the EG increased upper and lower body(all, p<.05). Balance of the EG increased(p<.05), but not in the CG. Pain significantly decreased in the EG post training(p=.000). However, both EG and CG did not significantly improve for QoL. Conclusion: Six weeks of water exercise program did induce significant improvement in physical fitness and pain control in patients with osteoarthritis.