Quercus mongolica, commonly known as Mongolian oak, is a species of oak native to Japan, southern Kuriles, Sakhalin, Manchuria, central and northern China, Korea, eastern Mongolia, and eastern Siberia. The species can grow to be 30 m tall.

The flavono-ellagitannins mongolicin A and B can be found in Quercus mongolica var. grosseserrata.