Background and aims: Mental health in nurses is always at risk because of stressful nature of nursing occupation. The aim of present study was to examine the association of organizational culture and job stress with mental health in nurses.Methods: Sample population of this cross-sectional descriptive study conducted in 2013 comprised all nurses of Hajar (peace be upon him) and Ayatollah Kashani hospitals of Shahrekord. 300 nurses were randomly enrolled as sample study. To measure the variables under study, we used questionnaire of job stress (Phillip L. Rice), 28-question questionnaire of general health (GHQ-28), and questionnaire of organizational culture (Denison) in addition to individual characteristics questionnaire. Results: In general, no significant reationship of organizational culture with job stress and mental health were found. But, there was a significant relationship between organizational culture and job stress (P<0.05). Demographic variables, being involved in job, mission, adjustment, and adaptability had a significant, negative associatin with job stres, and only adjustment had a significant associate in with mental health (p<0.05).Conclusion: According to the study results, it can be concluded that the use of cooperative organization culture in hospital benefits and cooperation of nurses in hospital affairs reduces stress. The assessment of organizational culture by hospital managers seems necessary to plan for organization and its success. Therefore, they can help nurses' mental health through holding courses for organizational culture promotion, creating a healthy environment, raising resistance power and individual adjustment, managing stress, and encouraging and supporting them financially. Using participatory organizational culture and having nurses participate in hospital affairs are helpful in decreasing job stress.