As it is known, the productivity of sunflower plants is strongly affected by the architecture of the plant, namely by the height of the plant as well as by the number, disposition, and surface of the leaves. The variability of the morphological indices of sunflower culture is a well-known phenomenon. This variability depends on the phenotypic stability of cultivated hybrids, and it is usually caused by environmental conditions that differ each year. Different genotypes will react differently to the same environmental conditions and will produce different phenotypic variability and different yield. This study was conducted to determine the variability of the number of leaves and the height of sunflower plants depending on genotype and climatic conditions. Trials were laid out in the test fields of the company "AMG-Agroselect Comert SRL", located in the city of Soroca, during the years 2019, and 2020. We studied 25 sunflower hybrids created within the same company. Plant height is an important indicator that determines the technological properties of sunflower hybrids. Thus, the average height of all genotypes in 2019 is 168.3 cm, and in 2020 - 150.1 cm. The unfavorable climatic conditions in 2020 led to a decrease in plant height, on average by 18 cm, which is 11%, but this decrease is not uniform for all genotypes. To determine the homogeneity of the populations of each genotype, we calculated the coefficient of variation (CV). Thus, the coefficient of variation of the height of all genotypes is 0.6% in 2019 and 1.4% in 2020. Despite the increased homogeneity according to this index, we want to mention that practically all genotypes have higher homogeneity in 2019 than in 2020. In some genotypes, based on the conditions of 2020, the number of leaves decreases by 3 leaves compared to the same index in 2019. But still in most genotypes the decrease is only 1-2 leaves. Which allows us to say that despite the different climatic conditions in 2019 and 2020, the number of leaves per stem does not vary too much. The coefficient of variation after this index increases slightly in 2020, which allows us to admit that unfavorable conditions reduce the homogeneity of populations by number of leaves. If in 2019, the average CV does not exceed 2.8% and the maximum value of this index is 3.4% then in 2020 the average coefficient of variation for all genotypes is 3.9%, and some hybrids reach a CV equal to 6.3%. As a conclusion, unfavorable environmental conditions reduce not only the high and number of leaves in sunflower hybrids, but also the phenotypic uniformity of entities within a genotype.