Objective: To assess the intensity and frequency of moral distress in mental health nurses in Brazil. Method: Cross-sectional study with 173 nurses from the Psychosocial Care Network in Brazil. The Brazilian Scale of Moral Distress in Nurses, adapted for the context of mental health, was used. For data processing, descriptive and inferential statistical analysis was used. Results: Mostly moderate levels of intensity and frequency of moral distress (medians between 2.25 – 3.73 and 2.00 – 3.22, respectively) were observed, with emphasis on the factors working conditions and social conflicts. Conclusion: The level of moral distress evidenced in mental health nurses in Brazil reflects the dimension and amplitude of the phenomenon in different points of the Psychosocial Care Network. The relevance of discussions on coping strategies for moral distress is highlighted, articulating elements such as sensitivity, resilience, and moral courage, so that ethical deliberation is applied in care and management settings.