This paper deals with the new advances made in recent years in the study of mineralogy, petrology, geochemistry and metallogenesis of the Bayan Obo ore deposit. In mineralogy, besides the previously-studied more than one hundred minerals, a lot of other minerals have been found and studied in succession, which include niobanatase, niobian perovskite, crichtonite, brockite, beiyunoboite,unnamed new species of fluorocarbonate, perrierite, magbasite and taeniolite. New relations of minerals, mineral paragenesis and replacement have also been found. In petrology, fenite and fenitization have been identified,and the existence of igneous carbonatite has been confirmed. In geochemistry and ore deposit genesis, the idea is put forward that REE and RE mineralizations are genetically related to carbonatite magaa atic activity. This idea, however, remains to be verified through further thorough investigation and various means of exploration. The results of our recent work have deepened the study of mineralogy, petrology, geochemistry and metallogeny of the Bayan Obo deposit.