The Bayan Obo giant REE-Nb-Fe deposit is the one genetically related to igneous carbonatic rock. Rare earths, niobium and iron were enriched from carbonatitic magma intrusion stage, altered country rock stage (fenite), to late-stage hydrothermal stage. Therefore, the Bayan Obo deposit is not a unitary type of deposit, but a mixed deposit containing REE-Nb-Fe carbonatite-type mineralization, REE-Nb-Fe replacement alteration, and hydrothermal effect. The deposit of such kind is very rare, and thus can be called Bayan Obo-type deposit. Based on age data published, the formation time of larges-scale carbonatite of the Bayan Obo deposit and the peak period of associated rare earth mineralization are around 1.3 or 1.4 Ga. The Caledonian tectonic thermal event had wide and extensive effect on this area, resulting in the development of large folding, thrust faulting and ductile shear, and extensive fluid metasomatism and regional hydrothermal activities. Isotopic composition systems of some rare earth minerals were relocated, suggested by disagreement of Sm-Nd ages and Th-Pb ages. Alkaline rock is not only present at basement complex of this area but at subsequent 1.3 or 1.4 Ga carbonatite of Bayan Obo Group. Current data available at least shows a genetic relation between alkaline complex and carbonatite. The basement complex in this area indicates that there existed an arc mass at the Bayan Obo area at 2.0 Ga, and during the Paleoproterozoic time (2.0~1.9 Ga) the Bayan Obo area experienced a complete orogenic process from passive continental margin to accretion collision of active continental margin.