Based on an analysis and study of the development of medical geology and geoheritage, the authors put forward for the first time the concept of medical geoheritage. Medical geoheritages in China are mainly distributed along the zone from Northeast China through Taihang Mountain, Loess plateau, Wuling Mountainand Sichuan basin to Yunnan-Guizhou plateau, with complex topographic characteristics and fault tectonic belts. Medical geoheritages can be classified into five types on the basis of pathogenic elements, namely, selenium deficiency (Keshandisease, Kaschin_beck disease), selenosis, iodine deficiency disorders (endemicgoiter), endemic fluorosis and carcinogenic geochemical elements. With natural geological attributes and scientific values as the main evaluation factors, the authors built the assessment system of medical geoheritage. The assessment of the selenosis medical geoheritage in Enshi indicates that this assessment system is practicable and operable