The F2 population was developed by crossing the adaptive yield variety of soybean with a variety without the Kunitz trypsin inhibitor in the mature grain. From the segregating F2 population 48 plants were taken. Their seeds were used to set up field experiment; part of the seed was saved for full-sib (FS) crosses. After yield testing, three lines marked as L6, L30 and L38 were chosen. Two FS cross combination, using saved seeds, were made (L30 x L38 and L6 x L30). Progenies of soybean full-sibs (FSF1:2) and each mother plant (F3:4) were grown, to make enough seed for testing in the field experiment. Data obtained in this experiment were processed to determine correlations of grain yield and other studied traits between mother's and proper full-sib progenies, using simple correlations and Spearman's rank correlations. A significant correlation into examinated traits between two types of progenies does not found, except for stem height and 1000 grain weight in the FS combination L30 x L38. The lack of correlation of plant characteristics between progenies of full-sibs and their mothers indicated the influence of lines used as fathers component. In both combinations of FS crosses, FSF1:2 progenies with better yield than the adapted parent (one without Kunitz trypsin inhibitor) were identified, which are considered promising for the further process of creating new varieties.