Mongolia is one of the biggest Asian countries and unique by its environmental traits. This always attract the attention of naturalists and other specialists. The soils studied are: The mountain taiga cryomorphic, derno taiga, mountain forest dark colored derno soils, mountain forest - steppe, chernozem, dark kastanozem, light kastanozem, pale brown desert – steppe, arid brown semidesert and alluvial meadow soils. The most common Actinomycetes in soils are the streptomycetes. Selective procedures for isolating the actinomycetes of rare genera from soils have been developed.They include the pretreatment of soil samples with heat and the addition of antibiotics into the nutrient medium. Data on population and taxonomy of actinomycetes in soils of Mongolia show that complexes of soil actinomycetes reflect specific features of the environment and the character of pedogenesis in these soils. The taxonomic diversity of actinomycetes in the steppe and desert ecosystems of plain territories is higher than that in the mountain and meadow ecosystems. Twelve genera of actinomycetes have been identified in the actinomycetal complex of soil samples of Mongolia. The rare actinomycetes are: Saccharomonospora, Saccharopolyspora Microbiospora, Microtetraspora, Streptosporangium, Thermomonospora, Actinomadura, Nocardioides, Nocardia and Dactylosporangium were isolated. The genera Streptomyces and Micromonospora predominate in the actinomycetal complex of soil samples of Mongolia. The genus Micromonospora is rather frequent in all the studied soils. The results also showed that selective procedures are especially efficient for isolating the representatives of rare genera of actinomycetes from soils. The use of selective methods for separation and identification of actinomycetes in soils makes it possible to specify those genera that produce antibiotics and other biologically active substances. Keywords: Identification, Actinomycetes, Soils, Mongolia.