Abstract: The Jehol Biota is a well-known Early Cretaceous paleontological fossil group distributed in eastern Asia, with a geological age of 120-131 Ma. Early studies suggested that Jehol Biota was mainly distributed in northern Hebei and western Liaoning of China. It was not until the special regional geological research was carried out in the 1980s in Inner Mongolia that many new fossil distribution areas and important fossil sites of Jehol Biota were discovered. The distribution areas, occurrence layers, assemblage differences and evolution rules of paleoclimate and paleoenvironment of Jehol Biota in Inner Mongolia are defined, and the restriction and synergic relationship between the evolution of Cretaceous sedimentary paleogeography, paleoclimate and paleoenvironment and the radiation evolution of Jehol Biota in Inner Mongolia are further clarified through the study on the fossil distribution characteristics and stratigraphic correlation of Cretaceous Jehol Biota in eastern and western Inner Mongolia.