Abstract. The purpose of the study was to study the effectiveness of microbiological preparations on the growth characteristics of Sudan sorghum under the conditions of the Vologda region on the background with and without fertilizers. Methodology and methods. Research work was first carried out in the Vologda region in the experimental field of FSBSI “Vologda Research Center of the Russian Academy of Sciences” in 2022. Biopreparations based on living cells of microorganisms were used, the basis of the drug “Naturost-Aktiv” consists of cell culture Lactobacillus buchneri, “Naturost-M” – Bacillus megaterium. The object of the study was Sudanese sorghum variety Zemlyachka. Small-scale field experiment included the following variants: control (1 var.), control + fertilizer (2 var.), biopreparation (3 var.), biopreparation 1 + fertilizer (4 var.), biopreparation 2 + fertilizer (5 var.). Repetition of the experiment – 3 times, the area of recording plot 5 m2. Indicators are presented by 4 counts per season. Results. The total bushiness in the variant with the “Naturost-Aktiv” increases by 35.3 %, an increase of 29.4 % to the control is noted in the variant “Naturost-Aktiv” + fertilizer. Productive bushiness was fixed in each variant, the maximum increase to the control was 45.5 % in the variant control + fertilizer. The greatest gain to the control of 42.5 % in the average area of the leaf surface was determined in the variant with the use of the drug “Naturost-M” and fertilization. Scientific novelty. For the first time a study on Sudan sorghum variety Zemlyachka in the conditions of the Vologda region using the biopreparation “Naturost-Aktiv” based on the cell culture Lactobacillus buchneri and “Naturost-M” – Bacillus megaterium on the background with and without fertilizers, which then can be recommended to increase the adaptation of plants and increase productivity, in turn Sudan sorghum can be recommended as a basic or auxiliary element of crop rotation.