Background: Osteoporosis is a metabolic bone disease and a growing global health problem that causes bones to thin and fragile. It is estimated that about two million people suffer from osteoporosis. According to the World Health Organization recommends regular physical activity is effective in preventing and while the results of some studies show about 65% of working women in Iran; do not get enough physical activity. This study aimed to determine factors associated with regular physical activity behavior for the prevention of osteoporosis in female employees Alborz University of Medical Sciences and was designed by HBM

Methods: This study is a cross-sectional study involving 217 female university employees, all of whom were studied with the consent of the census. Tools for data collection questionnaire that included demographic questions, knowledge and questions based on health belief model structures that had done

Validity and reliability. Data were analyzed using spss Edition19 and descriptive analytical statistics tests.

Findings: The results show that regular physical activity was 37/8%. Idependent t-test showed a significant difference (P< 0/001) knowledge and self-efficacy between the two groups (with and without regular physical activity). Logistic regression analysis showed that knowledge and self-efficacy are significant predictor of Physical activity behavior. In this study, a significant association was found between the income and physical activity

And the other factors such relationship wasnot found for physical activity.

Conclusion: According to lack of regular physical activity and considering the relationship between knowledge and self-efficacy with physical activity, the need to addressing this issue through educational programming based on related factors.