Аннотация:The distribution of rare earth element (REE) deposits and their resources through geological timehas been analyzed. The analysis is based on data on 103 deposits distributed around the world with a resource estimate of at least 100 000 t of lanthanoid and yttrium oxides. The variability in the formation of significant REE accumulations through geological time is demonstrated by comparing supercontinent cycles based on the ore resources of different types and ages. In the Kenoran cycle, only one deposit was identified in which the REE resources quantitatively exceeded the specified limit: a modified paleoplacer with initially detrital U–REE mineralization. The placer type is also represented in the Amasian cycle, but by deposits with different ore specialization. Carbonatite, hypergene in carbonatites, syenite, and alkali-granitic types are represented by deposits in all other supercontinent cycles. Significant foidic-type deposits were formed in the Columbian, Rodinian, and Pangean cycles; subalkali-granitic type deposits were formed, in the Columbian and Rodinian cycles; and ion-adsorption orebodies are known only in the Amasian cycle. On the geologicaltime scale, deposits of all types are distributed very unevenly. The maximum resources are estimated in deposits of the Rodinian cycle. The other cycles, not counting the extremely nonproductive Kenoran cycle, are 2–2.5 times inferior to the Rodinian cycle in this aspect. We have also analyzed the distribution in deposits of different types and ages of those light and heavy REE that are the most valuable on the world market. Deposits with a pronounced specialization in different groups of such REE have been identified. They occur in the sampling lists of deposits of all supercontinent cycles, except the Kenoran.