A survey to prevalence of subclincal mastitis (SCM) in some dairy cattle farms in state of Kuwait was carried out. For this purpose, a total of 200 quarter milk samples from apparently healthy dairy cows at Kuwait were investigated for subclinical mastitis using California mastitis test (CMT), Somatic cell count (SCC) and bacteriological isolation. The results revealed that the prevalence of subclinical mastitis was 45 % and bacterial culture was positive in 37.5%. SCC was assessed in 200 milk samples, the minimum and maximum SCC was 0.12 x 105 cell/ ml and 4.75 x 105 cell/ ml with the mean of 1.7±18.11 x 105 cell/ ml. The cultural examinations to determine subclinical mastitis causative agents revealed that the isolated bacterial strains in examined milk samples of cows were Staphyloccocus aureus, Streptococcus agalactia, E. coli and Pseudomanas aeruginosa with distribution of 37.6%, 20.5%, 19.4% and 3.2%, respectively as single infection from total 93 isolated bacterial strains. Meantime, there were mixed infection of (Staphyloccocus aureus + E. coli); (Streptococcus agalactia + E. coli) and (Staphyloccocus aureus + Pseudomanas aeruginosa) with the recovery rates of distribution of 8.6%, 9.7%, and 1%, respectively. Antibiogram profile of some representative field strains of Staphyloccocus aureus, Streptococcus agalactia, E. col and Pseudomanas aeruginosa isolated from subclinical mastitis cases to 11 different antibiotics. It revealed that all Staphyloccocus aureus, Streptococcus agalactia E. coli and Pseudomanas aeruginosa isolates were highly sensitive to enrofloxacillin, and Cloxacillin. However, it showed variable sensitivity degrees to other tested antibiotics. It could be concluded that subclinical mastitis constitutes a major economic and healthy problem for dairy herd in Kuwait.