A total 834 Ixodes persulcatus ticks and 641 small mammals from the areas of northern and southern Ural, southeastern and southwestern Siberia, and the Far East was examined on the presence of Anaplasma spp. and Ehrlichia spp. by nested PCR based on 16S rRNA gene with subsequent sequencing. A. phagocytophilum and E. muris DNAs were found in samples from ticks and small mammals in all studied areas. A. phagocytophilum DNA was revealed in 0.3–5.1% of ticks and 3.2–16.6% of small mammals from different regions, whereas E. muris DNA was found in 4.9–15.3% of ticks and 4.1–12.6% of small mammals. One I. persulcatus tick and one east-European field vole from the Siberian region were shown to contain ‘ Candidatus Neoehrlichia mikurensis’ DNA. A novel Ehrlichia species, closely related to Ehrlichia sp. EHf669, Ehrlichia sp. EH727, Ehrlichia sp. Tibet and ‘ Candidatus Ehrlichia shimanensis’, was found using molecular techniques in tissue samples of 14.4% of small rodents from the Far East.