It is known that one of the environmental factors for achieving the productive potential of plants is the hydric factor, which produces an enormous impact on agriculture. The creation of resistant genotypes to deficite of this factor at the moment presents an important topic for agriculture. The purpose of the research was to study the variability of pollen grains to genotypes of cereal crops in conditions of humidity deficiency; highlighting resistant genotypes. In the investigations, 12 genotypes of cereal crops – common wheat, triticale, rye and 3 reciprocal hybrids F2 of common wheat were involved. As a result of the microscopic study, the reaction of male gametophyte to the moisture insufficiency was determined by the action of polyethylenglycol (PEG). In genotypes under study, the size of pollen grains (GP) showed the high variability in optimal cultivation conditions. Thus, the rye genotypes are characterized by the smallest size of the GP, while the triticale and wheat genotypes have the character values higher. Under the influence of water stress on most samples, the GP perimeter was diminished, which is explained by the decrease of its dimensions due to the loss of water. Multifactorial variance analysis (ANOVA) demonstrated that the variability is determined by the action of PEG (54.7%), the genotype factor (41.6%) and their interaction (3.7%). The data reveal that in the reaction of cereal crops to moisture insufficiency, the role of genotype is quite significant, which is of the great practical importance by increasing the chances of success in identifying and selecting droughtresistant genotypes. Among the high-grade triticale varieties of GP, Ingen 33 and Ingen 40 can be mentioned, and among wheat hybrids - Apache x Cobra and Selania x Accent. So, the genotypes of cereal crops under study form pollen of different sizes. Among the genotypes analyzed on the basis of the pollen grain size stability were 2 triticale varieties (Ingen 35 and Ingen 40), 3 wheat varieties (Accent, Selania and Alunş) and 2 hybrid combinations with the participation of these varieties. Based on the obtained data on the stability of pollen grain sizes, the genotypes under study were categorized into resistance groups. Significant positive values of the correlation coefficient between the perimeter size in the control variant and the experimental variant (r = 0.77 **) were recorded. Thus, the ability of wheat, triticale and rye genotypes to maintain stable pollen grain sizes under hydric stress conditions can be used as a criterion for identifying and selecting resistant forms for their involvement in breeding programs.