Background & Objectives: Present study was conducted to survey the role of conscientiousness on job satisfaction and job stress considering mediating effect of perceived control. Methods: The statistical population of this study consisted all of Imam Reza hospital staff in Urmia, including nurses, GPs, specialists, and administrative staff. A sample of 248 individuals was chosen using stratified random sampling method. Data were gathered through standard questionnaires of Costa and Mc Crae’s conscientiousness, Brayfield & Roth’s job satisfaction, House and Rizzo’s Job Stress, and Tetrick & Larocco’s perceived control. Structural Equation Modeling was applied to evaluate relations between latent and measured variables in a conceptual model. Results: The results showed significant positive relationships between personality trait of conscientiousness and stress and Job Satisfaction. The results also showed that the relationship between personality traits of conscientiousness and Job Satisfaction and job Stress is mediated through perceived control. All regression weights were statistically significant in the concerned model. Conclusion: The results emphasize on necessity of reassessing the mediating role of perceived control on surveying the causal relation among personality traits of conscientiousness and its consequences.