Abstract: This study was conducted to determine the effects of some factors on Somatic Cell Count (SCC) and to investigate the relationships between these factors by SCC in Jersey cows raised at the Karakoy State Farm, Turkey. Quarter milk samples were collected at 28 days intervals and analyzed by direct microscopy. Data were evaluated by stage of lactation, udder quarter, parity and season by SPSS packet program. While data obtained in the latest stage of lactation had the highest level, effects of parity were significant (p<0.05 or p<0.001). No statistical difference was found among udder quarters. Besides, significant differences (p<0.01 or p<0.001) were determined among months and log SCC reached to highest level in December. Also, significant relationships (p<0.05 or p<0.001) were estimated in stage of lactation, udder quarter or some month groups. Thus, dairy owners are advised to spend more time on their herds, especially in later lactation period and rainy seasons.