Cows of the Lowland Black-and-White breed were studied by the method of discrimination conditioning according to the differentiation of seven colours in Oswald's scale (yellow no. 2, pink no. 5, red no. 7, violet no. 12, blue no. 15, green no. 21 and yellowish-green no. 23) from 16 shades of grey in Hering's scale. The high percentage of choices made leads to the conclusion that cows see colours as distinct entities. It was found from the percentage of positive reactions obtained to a given colour that a sequence exists in the cows' differentiation of colours. In connection with this the relativelability to distinguish the different colours listed above was established and estimated statistically (by t-test). Emphasis has also been laid on ethological variations with respect to differences in temperament and social status of the cows and the result of colour differentiation learning.