Object:　To　develop　a　typing　method　for　Staphylococcal　hemolysin　genes,　and　to　research　on　the　distribution　of　hemolysin　phenotype　and　hemolysin　genes　in　Staphylococcus　aureus　isolates　obtained　from　milk　of　cow　suffered　mastitis　and　to　analysis　there　relevance.　Methods:　The　hemolysin　pheno-type　was　oberserved　with　the　method　of　5%　blood　plate.　Hemolysin　genes　were　assessed　via　polymerase　chain　reaction.　Results:　The　typing　method　for　Staphylococccal　hemolysin　phenotype　and　genes　with　PCR　was　developed.　The　isolates　with　α-　hemolysis　are　56　in　129　isolates,　account　for　43.4%;　43　show　beta-hemolysis,　account　for　34.11%;　Another　29　isolates　showed　no　hemolysis　phenotype,　and　it　account　for　22.48%.　The　isolates　with　hla　gene　account　for　34.88%,　hlb　gene　account　for　42.60%.Conclusion:　In　the　hemolytic　phenotype,　α-　hemolysis　are　more　than　beta-hemolysis,　however　the　hlb　gene　detection　rate　is　higher　than　the　hla　gene.　The　distribution　of　hemolysin　phenotype　and　hemolysin　genes　is　not　a　corresponding　relationship　of　Staphylococcus　aureus　isolates　from　raw　milk　of　cow.　The　study　can　provide　a　basis　for　prevention　and　treatment　of　mastitis　in　dairy　cows　caused　by　Staphylococcus　aureus.　Staphylococcus　aureus　can　cause　a　range　of　illnesses　from　minor　skin　infections,　such　as　pimples,　impetigo　(may　also　be　caused　by　Streptococcus　pyogenes),　cellulitis　fol-liculitis,　carbuncles,　scalded　skin　syndrome　and　abscesses,　to　life-threatening　diseases　such　as　pneumonia,　meningitis,　osteomyelitis,　endocarditis,　toxic　shock　syndrome　(TSS),　bacteremia　and　sepsis,　it　can　also　cause　bovine＇s　mastitis.　S.　aureus　have　many　virulence　factors,　such　as　hemolysin　toxins,　Panton-Valentine　leukocidin　(PVL),　coagulase,　DNAse,　and　many　enterotoxins.　S.　aureus　not　only　threat　to　dairy　cattle　health,　but　also　endangere　the　safty　of　milk　categories　of　food.