It has been shown that adults with multiple sclerosis (MS) have less leg strength than their peers، as well as impaired balance، which led to an increased prevalence of falling in this population. The purpose of this study was to assess the effects of 8-weeks aquatic exercise training in balance، walking endurance and speed in women with MS. Twenty-one women patient with clinically-definite relapsing-remittent MS who were registered through the Isfahan MS Association (Iran) participated in this randomized clinical trial. Patients were randomized into two groups: exercise training (n = 10) or control (n = 11). The exercise training group participated in an 8-weeks aquatic exercise program of 45-60 minutes sessions، 3 days per week on alternate days; while the controls received standard medical care and follow-up. Balance، walking speed and walking endurance were measured by using the Berg Balance Scale، the 6-minute walk test (6MWT) and 6-minute walk time at baseline and after 4 and 8 weeks. The obtained data were analyzed using analysis of variance with repeated measures. After 2 months period، walking speed and endurance improved significantly in the exercise group compared with the controls (P < 0. 05). The exercise group showed significant improvement in balance، walking speed and endurance during all of the aquatic exercise periods compared with baseline (P < 0. 05). The difference in balance scores between the exercise and control groups was not significant after exercise-based water program (P > 0. 05). The results showed that aquatic exercise training in women with MS improves balance، walking speed and endurance. However، aquatic exercise training may lead to additional benefit beyond optimal medical treatments and should be a cornerstone in the management of all patients with MS.