The paper presents the results of studies on the nitrogen-fixing ability of soybean varieties depending on seed inoculation and fertilization. In today’s global conditions of ecological and economic crises, the attention to the potential of agroecosystems and minimization of the use of pesticides and agrochemicals is growing. Application of advanced forms of micronutrient fertilizers and inoculants is one of the most promising methods of crop production. The improvement of soybean cultivation technology with environmentally friendly components requires scientific justification, adaptation to specific soil and climatic conditions, and an assessment of their impact on the varietal characteristics of the crop. The research established that for the maximum formation of the symbiotic apparatus indicators, including the number and mass of nodules, their intensive functioning with the formation of the highest levels of total and active symbiotic potential, and the amount of biologically fixed nitrogen, it is necessary to combine pre-sowing seed treatment (with inoculant HighCot Super, micronutrient fertilizer Wonder Micro, and the seed protectant Maxim XL) and foliar nutrition with chelated fertilizers containing macro- and microelements (Wonder Yellow and Wonder Blue) against the background of applying mineral fertilizer at the rate of N20P20S9.. Under these conditions, the total number of nodules in Betina variety reached 50.4 nodules per plant, of which 43.8 were active, while in Vyshyvanka variety the total number of nodules was 48.5, with 38.3 active nodules per plant. The total and active mass of nodules in Betina variety was 586.5 and 469 mg per plant, respectively, while in Vyshyvanka variety, it was 581.3 and 465 mg per plant, respectively. Betina variety exhibited the longest total and active symbiotic period – 90.0 and 81 days, respectively, compared to Vyshyvanka variety – 88 and 79 days. The highest values of both total and active symbiotic potential were also recorded in Betina variety (37.3 and 26.2 thousand kg•days/ha) and in Vyshyvanka variety (34.8 and 24.6 thousand kg•days/ha. Similarly, the maximum amount of biologically fixed nitrogen was found in Betina variety (136.5 kg/ha) and in Vyshyvanka variety (127.7 kg/ha).