Osteoporosis is a condition characterized by a reduce amount of bone, leading to diminished physical strength of the skeleton and an increased susceptibility to fractures. Early identification of risk factors for osteoporosis and development of prevention programs is needed to halt the increasing incidence of the disease. The purpose of this study was to assess whether young women who participated in an osteoporosis prevention program based on the Health Belief (Rosenstock, 1966( demonstrated higher levels of knowledge, perceived susceptibility in osteoporosis, perceived severity of osteoporosis, perceived benefit and barrier of osteoporosis prevention behavior and adequate daily intake of calcium and smoking cession, reduction of alcohol and caffeine regarding osteoporosis prevention than young women who do not participate in such a program. A quasi-experimental design with one experimental group and one control group was used to test the efficacy of the osteoporosis prevention program. Data on Knowledge (13 items), health belief attitudes (21 items), and behaviors (15 items) were collected in the experimental and control groups. The experimental group participated in group work once with 2 weeks follow up, and met again after 2 months of the intervention. 70 young female students were nonrandomly assigned to an experimental group and to a control group to receive an osteoporosis prevention program. Young women in the experimental and control groups completed the osteoporosis knowledge test, the osteoporosis Health Belief Model, and their behaviors at three intervals. The experimental group received an osteoporosis prevention program. Both groups and experimental received a manual after finishing the intervention program with the experimental group. Instruction technique and structured questionnaire were used for data collection Percentage, mean, Standard Deviation and statistic analysis by simple independent t-test, chi-square and ANCOVA were applied in the data analysis. Results show that young female in the experimental group had significantly higher scores in knowledge, perception and improvement of behavior after receiving the intervention than their pretest scores while subjects in the control group had no change in scores. Conclusion: The osteoporosis program was effective in increasing knowledge and perception of osteoporosis prevention and increase improvement of behavior in osteoporosis prevention in this group of young women.