Background: Concerns about the environment have persisted over decades, and governments determinedly pursue the issue of environmental education. Designing an integrated curriculum is an effective approach to learning, participation, behavior, and critical thinking. Objectives: The presented study aimed to propose and validate an integrated model of environmental education curriculum for general medicine. Methods: This study was conducted using a mixed method (quantitative and qualitative). Data were collected using a questionnaire and via interviews. By using the Morgan’s table, the target population was determined to be 280 in Isfahan University of Medical Sciences (15 professors and 265 students). Results: The students had inadequate knowledge and low positive attitudes toward environmental education. Given the maximum consistency of the data obtained and the curriculum models provided by Silver and Alexander and Taylor and Kelvin, the integrated environmental education curriculum model was designed in 11 stages, including needs assessment, objectives, content, area determination, learning materials and resources, learning-teaching strategies, implementation and the role of professors, grouping, time, place, and evaluation. The proposed model was validated based on experts’ comments, and the content validity ratio was considered appropriate. Conclusions: Considering the integrated features of the proposed model, it applies to all stages of medical education and could foster effective interactions between students and environmental education during the seven-year study period, which confirms the efficacy of the model if implemented correctly. Considering the subjects of environmental education based on health-centered environment and the effects on physical, mental, and social health, the proposed model recognizes the contents of the current medical curriculum (i.e., disease prevention and treatment and the position of integration in organizing the content). In addition, it selects the contents of the model, which are reflected in its integrated approaches. The model composes of thematic knowledge, efficient knowledge, and functional knowledge in environmental education in medicine in the form of an integrated curriculum.