Environmental risk assessment (EAR) can be recognized as one of the important tools for the realization of sustainable development. The purpose of this research is to identify the types of environmental risks in Mazandaran province and provide a hybrid model in order to assess and prioritize them, which lead to better management of the environment hazards. In this research, 9 experienced manager from Mazandaran province's environmental protection agency and academic professors in this field were used as experts, and the Risk Breakdown structure (RBS) of environmental risk was defined based on their views at three levels. Then, using the DEMATEL technique, the importance of risk categories and their weight was determined. In the next step, criteria for risk assessment were identified and defined. Each risk was evaluated in each criterion based on the Taguchi Loss Function method, and their loss scores were calculated. According to the results, "cultural", "physico-chemical" and "economic" risk categories are more important than the others and affect them. Also, "Urban and Industrial Wastewater", "pest and disease of plants and animals", "excessive harvesting of forest and mineral resources", "discharge and disposal of wastes" and. . . were considered as the most important environmental risks respectively.