Twenty obese (BMI>30) women with an average age of 22.00 ± 1.50 years volunteered to participate in this study. They were randomly assigned to exercise (n=10) and control (n=10) groups. Before and after the training program, both groups were evaluated for anthropometric measurements and blood analysis. Bone mass density (BMD) was evaluated by using dual-energy X-ray absorptiometry (DXA) at the hip and spine (L2- L4). Each walking session was 30 min walking at 50-75% of maximal heart rate, 3 days per week, for 2 months. After 2 months, the exercise group showed no significant effect on BMD at the spine (L2- L4) and hip (p>0.05). However, there was a slightly increase in BMD at both regions, while the control group did not. Also, no change was observed in bloods factors. Percent body fat, fat mass and lean mass changes in response to training were significant in the exercise group (all p=0.000). As a result, it may be suggested that walking programs of longer duration and higher intensity can influence BMD and related factors in obese girls, however to achieve this result, more studies are needed.