Iranian cattle breeds are currently under-represented in studies regarding genetic variability and conservation effort even though they are settled in a region that is believed to be one of two ancient cattle domestication centres. This study provides first population genetic parameters for eight Iranian cattle breeds collected from across the entire country to highlight the necessity for conservation programs. High density genome-wide SNP chips were used. None of the Iranian breeds showed a decreased heterozygosity compared to outgroup breeds (Holstein, Jersey, and Brahman) and inbreeding coefficients were low. Nevertheless, estimated effective population sizes were <10 for the Mazandarani, Sarabi, and Kermani breeds and it is predicted that most of the genetic variability will be lost within 20-30 generations if no intervention measures are taken. Effective population size estimates varied between chromosomes with occasional extremely high values, especially for Najdi, Pars, and Kermani which have high proportions of indicine ancestry as represented by the Brahman outgroup.