A total of 1512 milk samples from udder halves was collected at monthly intervals from 189 line 05 dairy ewes throughout milking periods. Each ewe was tested 4 times. Milk composition was examined in terms of somatic cell contents (SCC) in ewe milk in three groups: group 0 consisted of ewes that on each test day had ≤250 × 10³ cells/ml in left and right udder halves, group 1 comprised ewes with ≤250 × 10³ in one half of the udder and >250 × 10³ cells/ml in the other half, whereas group 2 contained ewes that had >250 × 10³ cells/ml in the left and right udder halves (also on each test day). SCC in milk from one or both halves of udders exceeding 250 × 10³ cells/ml resulted in a statistically significant (P<0.01), 20.7%, decrease in daily milk production. Correlation coefficients between SCC and fat and protein percentages in milk were positive and equaled 0.24 and 0.18, respectively. A negative value of the correlation coefficient was recorded between log SCC and lactose percentage (-0.49).