In the study, we assessed the genetic diversity and genetic structure of Hungarian populations of different large, bodied pigeon breeds, and the extent to which international breeds influence the genetic stock of Hungarian breeds. The low number of items could have affected the results of the analyses, so it would be worthwhile to repeat the tests with a larger number of items. Although there is no significant difference between Hungarian and Squab breeds based on the source of variance, but the results showed genetic diversity among the Hungarian breeds, differing in nucleotide composition between the two groups. The nucleotide composition of DNA was compared between Hungarian breeds and Squab breeds, with slight variations observed in the percentages of cytosine, thymine, adenine, and guanine between the two groups. Understanding nucleotide composition is essential in evolutionary biology, population genetics, and genomics. A pairwise comparison of Fst values revealed genetic differences between breeds, with Runt pigeons showing the highest genetic variance, but this value was also low, and Buga pigeons showing the lowest. The AMOVA test identified three sources of genetic variation in the Hungarian and Squab breeds. In these results I get negative value in percentage of variance, which is not very common. In conclusion, our mtDNA COI region can be effectively used to assess the genetic diversity and genetic structure of Hungarian pigeon breeds and other domestic pigeon populations. The information from this thesis will provide useful input for mapping the genetic background of large-bodied pigeon breeds in Hungary and may also serve as a starting point for the genetic improvement of domestic pigeon breeds and the development of conservation/breeding programmes for native breeds. Overall, the results of this study demonstrate that the pigeon breeds analyzed from Hungary exhibit a high level of genetic diversity, which is important for their conservation and breeding. The differences in nucleotide diversity between breeds could reflect variations in their demographic histories, breeding practices or environmental factors. The study provides a baseline for future studies of genetic diversity in pigeon breeds and highlights the need for continued efforts to preserve genetic diversity in these important domesticated bird populations. Genetic characterisation should be carried out with a larger number of elements in the future. These results are also useful for developing conservation strategies and understanding the evolutionary history of pigeon breeds. Understanding genetic differentiation and variation is essential in population genetics and conservation biology.