Abstract: During the 4^th—6^th century AD, there were frequent cultural exchanges between the Western Regions and the Central Plains, among which the spread of Buddhist culture from west to east made Kizil Grottoes in Xinjiang and Yungang Grottoes in Shanxi successively entered a prosperous period of construction. Based on historical documents and existing archaeological research results, this study analyzed the historical background and cultural blending between the Western Regions and the Central Plains during this period, enumerated the types of mineral pigments appearing in the representative murals in Kizil and Yungang Grottoes, compared the mural pigment layer, ground battle layer and expression form between the two places, and discussed the use of lapis lazuli and celestite. The study found that although these two grottoes have similar historical framework and excavation background, they have evolved different creative styles because of the great differences in their respective regional cultures. They are the carriers of cultural blending from the Western Regions to the Central Plains and from the Central Plains to the Western Regions, and have certain comparative research value.