Avian influenza (AI) H5N1 viruses are zoonotic agents that cause high mortality rates in humans and poultry. In this study, some molecular characterizations and phylogenetic analysis of Hemagglutinin gene of H5N1 isolates seen in our country in 2006 were performed. Thus, it is aimed to determine the pathogenicity levels of those available isolates and whether they have the ability to transmit from person to person and establish the evolutionary relationships to some other viruses circulated in Europe, Asia and Africa. In the scope of the study, seventeen H5N1 isolates that were isolated from various Avian species were used. After the isolates were regenerated and produced in specific pathogen-free (SPF) embryonated chicken eggs, chorioallantoic fluids of the eggs were collected and RNA extraction was made, and the enzyme cleavage and receptor binding site of the hemagglutinin gene was replicated using RT-PCR. After this process, the enzyme cleavage site of the Hemagglutinin genes and the amino acid sequence of the receptor-binding site were determined by the BioEdit program. As a result, it was determined that all the seventeen isolates are High Pathogenic AI viruses. In addition, the sequence analysis of the receptor-binding site indicated that seventeen isolates did not have any mutations in the relevant amino acid positions. Also, our isolates were classified as clade 2.2 and clade 2.2.1 and were closely related to European and Asian isolates. Moreover, it is found that our isolates are not capable of transmitting from person to person; However, due to the virus traits, it has been concluded that the molecular and antigenic characteristics of the virus should be determined in places where the disease occurs since it is still circulating in some parts of the world and can be transported with migratory birds.