Aim <p>Since there is no short screening instrument that measures the most important factors for assessing an organization’s health situation, this study aims to develop and validate an instrument for assessing the state of health of organizations. The instrument should enable a quantitative screening of an organization’s health situation on individual mental health, teamwork, supportive leadership, and healthy culture and may be beneficial to professionals in health promotion settings.</p> Subject and methods <p>The study used a cross-sectional design and yielded 790 complete responses from employees from seven organizations across different sectors. The questionnaire was designed to measure four key dimensions of organizational health: mental health, good teamwork, supportive leadership, and healthy culture. Exploratory factor analysis was used to develop reliable scales. To better understand the nature of the interrelationships between these dimensions, a mediation model was tested using regression analysis.</p> Results <p>Factor analysis showed that after removing some items from the questionnaire, supportive leadership, good teamwork, healthy culture, and mental health formed independent, distinguishable factors. The scales measuring these constructs were reliable. Supportive leadership, good teamwork and healthy culture correlated positively with mental health. The relationship between supportive leadership and mental health was mediated by good teamwork and healthy culture.</p> Conclusion <p>The study successfully developed a reliable organizational health questionnaire that provides a practical tool for professionals. It enables a quick assessment of organizational health and identifies problem areas for further analyses. Future studies should use a multilevel design to not only collect data at the individual level.</p>