The article presents the results of long-term studies of soybean variety variability in terms of valuable economic traits (yield components) and yield under different hydrothermal growing conditions. Varieties that ensured high stability of yield components were identified using mathematical and statistical analysis methods. The highest repeatability coefficients for the number of productive nodes were observed in the Desna variety – 0.82, with a coefficient of variation of 12.7% and 16.1 productive nodes; in the Bilyavka variety – 0.81, with a coefficient of variation of 12.4% with an average value of 16.7 units. The variability of the yield level during the years of research was high, with the repeatability coefficient ranging from 0.55 to 0.75, which is quite natural given the large number of formative traits that contribute to its determination. The highest repeatability coefficients were observed in the varieties Femida – 0.75, coefficient of variation – 10.7%, and yield – 1.88 t/ha; Amethyst – 0.73, coefficient of variation – 11.4%, yield – 1.88 t/ha; Vezha – 0.72, coefficient of variation – 11.4%, yield – 1.89 t/ha. It should be noted that these varieties were distinguished by high values of repeatability coefficients for the weight of 1,000 seeds, in particular, Femida – 0.91, Ametist – 0.93, Vezha – 0.80; as well as for the number of productive nodes, pods, and seeds: Femida – 0.69; 0.52 and 0.55, and Vezha – 0.68; 0.56 and 0.57, respectively. Thus, ensuring a stable level of soybean yield is determined by the formation of stable indicators of the elements of the soybean yield structure of each variety in particular.