In the present study, a total of 100 clinical samples were collect and processed from patient suffering from breast infection or mastitis carried out in two main place in Babylon province i.e. Al-Hilla General Teaching Hospital (breast cancer consolation) and outpatient clinics, which they were diagnosis as breast infection or mastitis by the physician after the medical tests included the clinical examination of the patient and U/S, mammography). Also PCR amplification test for universal gene ,uni678 gene, uni1870 gene, and sau gene were used for direct detection of bacterial isolates from clinical samples and the result showed that out of 100 samples ,only (37,40)sample contain gene to universal primers , uni-678(210) bp and uni-1870(438)bp respectively. Polymerase chain reaction (PCR)used for detection virulence genes that coding to hemolysin of S.aureus isolates ,it was found that positive results were showed for hla,hlb, ,hlg and hld that with percentage ,(45.4%,(32%),(36%) and (54%) respectively.