Purpose: The purpose of this study was to exam me the effects of aquatic exercise on pain, fatigue, body composition, physical fitness and psychological variables in women with arthritis. Method: With a quasi-experimental design, 37 women who had arthritis were assigned into an experimental group (n=19) or a control group (n=18). Aquatic exercise consisted of one hour of exercise in water, two days per week, for six weeks and a self-help process. Measures included physiologic and psychological variables before and after the exercise. Data was analyzed with the SPSS WIN using descriptive statistics, t-test, and ANCOVA. Result: The mean age of the subjects was 59 years in the experimental group and 52 years in the control group. Pretest scores in outcome variables were similar in both groups except BMI and body fat(%). After controlling for age, shoulder flexibility scores in the experimental group improved more than the control group (Rt: F=10.58, p=.003; Lt: F=5.91, p= .02; Waist: F=4.95, p= .03). Depression scores in the experimental group decreased (F=12.96, p= .001), and self efficacy and quality of life improved more than the others (F=5.07, p= .03; F=6.9l, p= .01). Conclusion: Aquatic exercise can improve waist flexibility and shows consistent findings of improved shoulder flexibility and psychological function in women with arthritis.