Introduction: Present study was conducted in order to evaluate the relationship between NEO-PI-R personality test with the questionnaire SCL-90-R, aiming at evaluation of this test efficiency in investigating the indices related to mental health that are considered as the primary symptoms of common psychiatric disorders. Method: 500 students of Tabriz & Shiraz Universities were selected through simple random sampling procedure in 2008-9. NEO-PI-R & SCL-90-R tests were carried out on participants. For analysis of data the regression analysis, Pearson Correlation Coefficient and independent T-test were used. Results: The neuroticism (N) factor with the highest power, predicted all indices related to SCL-90-R. Totally, the main personality factor had the highest and the best predictions for somatization, obsession & phobia indices, respectively. Conclusion: The scales and main factors of NEO questionnaire can be used as indices for evaluation of mental health, and even for investigating the explicit symptoms of axis I psychiatric disorders.