A study was conducted on 594 healthy buffaloes belonging to Murrah, Surti and Nili-Ravi breed to find out the basal values of somatic cell counts (SCC) in milk with respect to breed, stage of lactation, parity, season and level of production. The relationship of SCC with milk yield and composition was determined using correlation coefficient. The average SCC in Murrah, Surti and Nili-Ravi breeds was 1.096, 0.855 and 0.969 x 105 cells/ml, respectively. SCC was highest during early stage of lactation, in rainy season and in animals with higher parity. The milk yield was negatively correlated with SCC. The milk SCC was significantly (P<0.01) but negatively correlated with fat, protein and SNF content of milk. The comparison of SCC categories within sub-clinical mastitis negative buffaloes, revealed that as SCC increased from 0.50 to greater than 1.50 x 105 cells/ml milk there were losses in milk yield (3.43 %) as well as the content of milk fat (11.30 %), protein (5.09%) and SNF (3.59%).