Abstract: 1728 mammary regions from 451 production cows reared in a cattle farm of Baotou City in Inner Mongolia were detected, and the isolation identification and drug sensitivity test of pathogen were made in the experiment. The result showed that there are 252 cows suffered from recessive mastitis and the positive rate was 55.9 %; there were 1728 effective mammary regions, 480 positive mammary region and the positive rate of mammary region was 27.8 %. Staphylococcus aureus, streptococcus, Escherichia coli, corynebacterium, salmonella and Staphylococcus epidermidis were isolated from the milk of detected positive mammary region of rec, essive mastitis, resp. The detection rate of infectious bacteria of S. aureus and Streptococcus in the detected bacteria were higher. From the result of drug sensitivity test, cefazolin and quinolone drug had high sensitive to other bacteria except salmonella, and the common drugs showed tolerance to a different degree; the euphorbia Chinese herbal medicine had certain sensitivity to streptococcus, poor antibacterial effect on E. coli and staphylococcus, no antibacterial effect on corynebacterium and salmonella; Ruyanjinzhen was the mixture of Chinese traditional and Western medicine, which had better antibac, terial effect on the 6 pathogenic bacteria.