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Background & objectives: In the third millennium, human resources are the most valuable asset of the organization. So the empowerment of human resources is one of the most important organizational measures and has unique role in success of the organization to achieve its goals and improve the effectiveness and efficiency of human resources. The aim of this study was to examine the factors influencing the development of mental abilities in employees.
Methods: In this practical, descriptive and correlational study; out of 440 staff employed in the headquarters of the Ardabil university of medical sciences in 2015,  205 subjects were selected using multi-stage random sampling method (stratified, cluster and random). Data were collected using empowerment questionnaire and survey of factors affecting psychological empowerment questionnaire. Data were analyzed by statistical tests such as Pearson correlation and multiple regression.
Results: Results analysis showed that all three studied variables (individual factors, group factors, and organizational factors) play important role in explaining the dependent variable (psychological empowerment). These three variables correlate with the dependent variable at R=0.51. There is also a significant difference in degree of these factors. Organizational factors (β=0.248) had the highest and individual factors (β=0.195) had the lowest effect on psychological empowerment.
Conclusions: In general, although various aspects of Spritzer's model, as the basis for this study, was approved by the relevant tests, but the importance and priority of these characteristics in the pattern of psychological empowerment of human resources in Ardabil medical university headquarter was different and depended on its conditions. So one can improve psychological empowerment of human resources through increasing staffs confidence, facilitating their participation in achieving organizational goals, clarify roles and duties and providing necessary information.