Milk protein genetic polymorphisms of the genus Bos provoke a significant scientific interest, mainly associated with their evolution, population structure, breeding and hybridization. The aim of present study is to investigate the influence of the genetic variants of αS1- casein gene with respect to milk production and quality of native for Bulgaria cattle breed - Bulgarian Rhodopean cattle. A total of 87 unrelated animals of that breed were examined for genetic variants of the αS1- casein gene through PCR-RFLP analysis. The results showed that three genotypes BB, CC and BC were presented with 26.4 %, 2.3 % and 71.3 %, respectively. The frequency of B allele (62.1 %) was almost twice higher as compare with C allele of the gene (37.9 %). The effect of estimated genotypes on qualitative and quantitative milk traits could be summarized as follow: milk production and milk butter, BC>BB>CC; fat and protein contents, CC>BB>BC. The presence of correlation between genetic variants of αS1- casein gene and qualitative and quantitative bovine milk traits gives a reliable approach for selection of animals with desirable milk traits and genetic elaboration of that native breed as a part of national genetic fund.