Research indicates that managers’ active support is essential for the successful implementation of mental health-related organizational interventions. However, there is currently little insight into what subjective beliefs and perceptions (=mental models) make leaders support such interventions. To our knowledge, this is the first qualitative systematic review of this specific topic, and it considers 17 qualitative studies of managers’ perspective. Based on the theory of planned behavior, this review provides an overview of three action-guiding factors (attitudes, organizational norms and behavioral control) that can serve as starting points for engaging managers in the implementation of mental health-related measures and ensuring their success. Our results provide evidence that supportive organizational norms may particularly help to create a common sense of responsibility among managers and foster their perceived controllability with respect to changing working conditions. Our study thus contributes to a more differentiated understanding of managers’ mental models of health-related organizational interventions.