The article presents the results of the source studies analyses of the alphabetical lists of confirmed and ascribed nobles of the Ufa and Orenburg gubernias from the Russian State Historical Archive (RGIA). Imperially approved opinion of the State Council of the Russian Empire (January 2, 1861) ordered national noble assemblies to send annually to the Department of Heraldry of the Governing Senate “alphabetical lists of noble families during the year confirmed in their nobility by the Governing Senate” and “similar lists of those families, to which, in the course of the year, were attached some individuals.” Most of these lists are preserved in the materials of the “Third Department of the Senate” fond of the Russian State Historical Archive. The archives holds original copies of 39 reports and 65 lists, including 28 lists of confirmed nobles, and 37 — of ascribed, which were sent to the to the Department of Heraldry of the Governing Senate by the Orenburg Noble Assembly in 1862-1917; and 48 reports and 89 lists, including 41 of confirmed nobles and 48 — of ascribed, which were sent to the Department of Heraldry by the Ufa Noble Assembly in 1866-1917. These documents are written on plain paper on both sides of the sheet sized 22.2 (width) * 35.4 (height) cm. Most are handwritten. Reports of the Ufa Noble Assembly became typewritten from 1899 on, those of the Noble Orenburg Assembly — since 1911; lists of Ufa Noble Assembly became typewritten from 1897 on, of the Orenburg Noble Assembly — from 1908 on. The lists have a title page. Information about the nobles is given in tabular form. A list of confirmed nobles contains the following information: surname, name, patronymic of the person confirmed in hereditary nobility; date of the resolution of the Noble Assembly on declaring them a noble; part of the genealogical book, in which that person was entered; the date of receipt of documents for consideration in the Department of Heraldry; date and number of the confirming decree of Department of the Heraldry. The list of ascribed nobles includes such data as: surname, name, patronymic of the person added to the nobility; the date of the resolution of the Noble Assembly to ascribe the person to a noble family, confirmed by the Department of Heraldry; name, date, and document number(s) on the basis of which they were ascribed; part of the genealogical book, in which the family was entered; date and number of the decree of the Department of Heraldry of the Governing Senate confirming the family to rank among the nobility. The list was to be certified by signatures of the gubernia marshal of nobility, or those acting in that position, and by the secretary of the Noble Assembly. The list was not sealed. These documents are unique and quite valuable written sources on the history of the Russian nobility.