The objective of the research study was to compare the composition of fatty acids, with particular focus on the content of conjugated linoleic acid (cis9trans11 C18: 2) acid and trans C18:1 and C18:2, in milk as well as in kefirs and yoghurts produced from it. The analysis performed comprised raw milk, normalized milk as well as kefirs and yoghurts produced from it. A fatty acid profile was determined by a GC method using a 100-m capillary column with a CP Sil 88 phase. The technological process of producing kefirs and yogurts as applied to this experiment did not affect the profile of fatty acids in the fermented milk drinks under analysis. The composition of fatty acids in kefirs and yoghurts was similar to the composition of fatty acids in milk fat. In the fermented drinks examined, the content of conjugated linoleic acid cis9trans11 C18:2 (CLA) and trans isomers of C18:1 and C18:2 depended on their concentration in the raw material they were made of.