In this study the relationship between the level of nrtnc oxide and somatic cell count in the cow milk with mastitis in the milks of animals with mastitis determined according to the results of somatic cell count. In the study, 256 milk samples received from each breast lobe of Brown Swiss 64 milk cows of 4 - 5 age and in the middle of their lactation period. During the survey qualitative cell counting method has been used and according to results of somatic cell count (SCC) some groups have been established. 93 samples with 0-200.000 have established the control group, 46 samples with 200.000400,000 have established the trace group, 49 samples with 400.000-1.200.000 have established the 1st group, 33 samples with 1.200,000- 2.200.000 have established the 2 nd group and 35 samples with more than 2.200.000 somatic cell count m 1 ml have established the 3 th group. In the milk samples received from these groups nitric oxide and nitrite levels of milk have been determined through the spectrophotometry method based on Griess reaction. The average levels of nitric oxide were established in healthy group: 21,27±2.86 (imol/L. in trace group 22,55±3.09 umol/L, the degree of maslitis was getting increase they were established as {respectively 1 st, 2 nd and 3ra group) 27,42+2,54 (imot/L 30,75+2,62 nmoi/ L and 37,42+6.27 |iimol/L. While !he average nitnte levels were dedected in healthy milk 0,52±0,35 pmol/L. in trace group 0,52±0,43 nmotfL, the degree of mastitis was getting increase they were respectively established as (1st, 2 ^ and 3 rd group) 0,99±0,54 pmol/L 1,13±0.27 pmofL and 1,32+0,46 |imol/L. Regarding the nitrite levels in blood there was not any difference between control and trace groups. On the other hand there have been some differences observed between these and remaining 1 s', 2 ^ and 3 1x1 groups (P<0,05). There was not any difference between the control and trace group with respect to the amount of nitric oxide, it has been seen that other groups have showed significant increases between each other and with respect lo control and trace groups (P<0,05).