Goal. To determine the level of homozygosity of the active part of the population of the white-headed Ukrainian breed for one generation and 50 years of reproduction, as well as the possibility of using inbreeding to preserve the gene pool of the breed and increase animal productivity. Methods. The study was conducted on animals of the white-headed Ukrainian breed, divided into outbred and inbred. The first series of experiments determined the influence of unrelated and related selections of parental pairs, the second series studied the influence of the origin of the bull (the father of the offspring) on the manifestation of signs of productivity in outbred and inbred cattle. In both experiments, the group of inbred included animals whose inbreeding coefficient was Fx = 0.39–29.7%, and the group of outbred — who had no common ancestors in the pedigrees. In the third series of experiments, the influence of different degrees of inbreeding (moderate, close, and very close) on the milk productivity of cows of a specific origin was determined, for which the descendants of the bull Zlaka UA 673 were divided into 4 groups. Live weight of cows, milk yield for lactation, content and amount of milk fat in milk, age of the 1st insemination were determined. The level of inbreeding growth was calculated for one generation and 50 years of reproduction. Results. The advantage of inbred heifers in live weight in different growing periods compared to outbred individuals was established, especially at the final stage, which accelerated their physiological and economic maturity. The effect of inbreeding on the reduction of milk production in cows of individual bulls without statistically significant difference with outbred animals had been proved. There was a direct, medium and weak connection between milk yield during the 1st lactation with age and live weight at the 1st insemination. It was proved that the increase of the inbreeding coefficient from Fx = 0.78–2.93% to Fx = 12.5–29.7% in the daughter offspring of the bull Zlaka UA 673 significantly increased milk productivity for 1–2 lactations. It was found that in the modern, active part of the population of the white-headed Ukrainian breed, inbreeding can increase by 1.68% in a generation, and by 16.5% in 50 years of reproduction. Conclusions. When breeding Ukrainian white-headed cattle, which currently has 300 cows and 11 bulls, it is impossible to avoid a related selection of parent pairs. With this in mind, inbreeding can be used as a method of preserving the gene pool of white-headed cattle in the context of preserving the biodiversity of wildlife. The use of close inbreeding is preferable to moderate and close.