**Abstract**

This study includes natural hazards and environmental problems caused by gypsum on and near the soil, water, and structures. These are karst-specific deformations (caves, fractures, cracks) naturally occurring in gypsum areas, and the problems of salinization, corrosion, erosion, soil and water pollution that occur as a result of dissolution caused by the contact of gypsum with water. In particular, it has been determined that various transfer routes/lines that facilitate human life cause problems on substructures/superstructures resulting from their passage in gypsum areas or on substructures/superstructures (road, buried pipe, building) resulting from the spread of urbanization on this unit, and these have various risks. As a result of these events that have been proven by various studies, it has also been observed that gypsum causes natural hazards and has environmental impacts on human/plant/animal life and living environments and it has also been determined that the quality and sustainability of life/living environment decreased. Therefore, in this study, it has been put forward that gypsum areas pose a risk for the life of all kinds of living beings and that the choice of gypsum areas in the site selection for urbanization will always be risky with respect to natural hazards and environmental problems.

**Keywords:** gypsum, karst, Sivas (Turkey), natural hazard, environment
