Background: Promoting mental health and preventing staffs from mental health problems are important tasks for military commanders and mental health professionals in the military organizations. This objective requires the establishment of information networks and systems of efficient data collection and determining the indicators of mental health in military personnel. This study was conducted to determine the mental health indicators in military personnel. Materials and Methods: This study was performed based on Q methodology in six stages: 1. Development of Q Sample Statements, 2. Selection of Participants (30 professionals in the Military organizations) for the Q Sort using Judgement Sampling method, 3. Q-sorting in a 9-degree range based on indicators' significance, 4. Data entry using SPSS, 5. Statistical analysis through the extraction of Q sorts, (the Principal Components Analysis method was used), 6. Factor Interpretation. Results: 32 mental health indicators were determined in mental health system of military forces in four categories: mental health status, mental health factors, spiritual and health behaviors, using health services. Conclusion: This study, as a basic research, was carried out to develop mental health indicators in military forces. The results expressed the present mental health status of military organizations. In addition, indicators obtained in this study can be used in the present mental health status assessment, future plans and policies, mental health information updates, scientific comparisons, and mental health services supervision and assessment aiming mental health quality promotion in military forces.