Abstract: USP9Y gene is closely associated with sperm production, and it plays a very important role in animal breeding. Using cow USP9Y gene sequence included in NCBI as primer design,USP9Y gene was screened by PCR technology in Cashmere goats BAC library, cloned and determined in this study to further investigate the mechanism of goats sperm production and improve the breeding rate.We compared the obtained fragment with the sequences of other species in NCBI.The alignment results showed that the homologies with cattle and felwa cat respectively were 98% and 95%, the homology with Homo sapiens,Macaca mulatta,chimpanzees and other species was 89%. It indicated that USP9Y gene sequences had a certain conservative in the evolutionary process.The study will lay a basis to further gain the total sequence of USP9Y gene through sequencing BAC,research gene function and fully develop the economic value of Cashmere goats.

Key words: Cashmere goats; USP9Y; BAC; screening; identification