The studies were conducted in 2015–2017 in the Right-Bank Forest-Steppe on a typical low-humus chernozem. The influence of the primary tillage and the influence of soybean preceding crops on the formation of its productivity and soil fertility are determined. The action of the studied factors on the change in the agrophysical properties of the soil, the formation of available moisture in the soil and its water consumption parameters has been established and justified, the volumes of organic matter and nutrient supply to the soil have been calculated, balance of nutrients during its cultivation. An economic and energy assessment of soybean cultivation is given depending on the primary tillage and choice of preceding crops. It was found that soybean plants most effectively spend moisture after winter wheat when chisel cultivating 20–22 cm – 390 m3/t, and most costly after corn for grain and sunflower when 6–8 cm disking and direct sowing, respectively 602 and 550 m3/t and 623 and 621 m3/t. When placing soybeans after soybeans, the moisture consumption at the level of 408–409 m3/t provided soil treatment with chisel at 20–22 cm and disk harrow at 12–14 cm. There was an increase in soil density from sowing to full ripeness without exceeding the optimal values (1,30 g/cm3) during plowing and chisel cultivating to a depth of 20–22 cm. For shallow and surface tillage, density was formed within 1,36–1,39 g/cm3, with a certain increase in the variant of direct seeding (1,38–1,43 g/cm3). An effective measure in the cultivation of soybeans is symbiotic nitrogen fixation, which is from 78 to 130 kg/ha. The intensity of nitrogen balance in the cultivation of soybeans after cereals is 91–100 %, corn for grain – 99–109 %, sunflower – 96–108 % and soybeans – 100–105 %. The studied factors ensured the formation of a positive balance of phosphorus at the level of 40,9–49,6 kg/ha and potassium at the level of 54,6–88,4 kg/ha per year. It is established that for the formation of economically and energetically expedient, adequate to the resource content of soybean seed yield should be used chisel tillage for 20–22 cm and place soybeans after cereals. The soybean yield will be at the level of 3,50–3,70 t/ha. Of particular note is the use of soy as a precursor to soy. On average over the years of research, the highest yields of 3,42 t/ha are provided using disc harrowing by 12–14 cm. When growing soybeans after corn for grain and sunflower, it is necessary to carry out shelf tillage by 20–22 cm, which ensures soybean yields 2,83–3,12 t/ha.
