The author of the article attempts at assessing the number of nobles (boyars) in pre-Mongol Rus’. He uses the data from non-narrative sources, first of all from the treaty of 944 between Rus’ und Byzamtium, and from those chronicle’s reports which indicate directly to numbers of boyars in certain local centers – these reports are coming back to the 13-14th centuries. He concludes that the ruling classes in the different polities on the territory of Rus’ during the 10-14th centuries (from the Dnieper Rus’ of the middle of the 10th century to independent princedoms-lands of the 12-14th centuries) consisted of no more than 20-30 persons. The number of the whole estate of boyars at the beginning of the 13th century was approx. 1500 persons (not numbering members of their families).