Ukraine is one of the European and world leaders in soybean cultivation. According to some estimation, 30-90% of the crops area is used currently for cultivation of genetically modified varieties. As modified soybean areas are expanding, the potential nutritional threats related to this product should be thoroughly assessed. The influence of nutrition ration consisting of 20% of the thermo-treated genetically modified soybeans on postnatal development of rats has been investigated over two generations in comparison with nutrition by regular thermo-treated beans. The number of alive and dead newborns, average number of offspring and the survival rate has been calculated as well as general estimation of physical development of the newborn rats was made. The experimental results prove that the reproductive function of rats and the offspring development are not seriously influenced by nutrition with genetically modified soybeans within the first and second generations. No statistically reliable difference was found between the characteristic parameters of the experimental and control groups, which remained within their regular physiological limits. However, some decrease in the suckling age rats’ number was registered in the experimental group.