* M1, F2, M3, E4, D5 Abstract Background: With regard to the importance of mental health in student category particularly for military students, owing to the stress and tension in the military atmosphere which leading to insecurity, reducing the efficiency, and anxiety in these students, therefore this study has been done to investigate the prevalence of state and trait anxiety and its relationship with demographic variables in nursing students of elected military medical university. Materials and methods: In this descriptive study, 130 nursing students of elected military medical university were selected by census method. Data collection tools included the researcher made demographic questionnaire and Spielberger State-Trait anxiety inventory that included 40 questions. Statistical analysis was performed by SPSS software version 18 and descriptive statistics were calculated. Results: The results showed that 98.5% of the students had a moderate to high to extreme anxiety state and 98.5% of these students had moderate to very severe anxiety. There was a significant association between dormitory residency and state-trait anxiety, as the anxiety level was higher in dormitory resident student. Conclusion: Considering the high prevalence of anxiety and likely to exacerbate the problem in the period of responsibility, therefore screening methods and increasing students’ mental health in is essential. So, it is suggested that using methods for reducing anxiety such as improving the environment conditions.