The objective of this study was to evaluate the effect of conjugated linoleic acid (CLA) and thermal processing on chicken meat. The experiment was performed on forty eight 26-week old Isa Brown chickens randomly allocated to two (0.00% vs 0.75% CLA) dietary treatments. Breast muscles and thighs were thermally processed by the cooking techniques: boiling, roasting and frying. The fatty acid composition was determined in both chicken breast and thigh samples. Cooking losses and, consequently, total lipids, increased directly along with following cooking methods: frying > roasting > boiling. Regardless the CLA supplementation, the dry matter and total fat contents were unchanged in raw chicken meat. During processing, the contribution of fatty acids (g · 100 g⁻¹ of total fatty acids) was changing. Regardless the CLA supplementation, the fatty acid content (mg · 100 g⁻¹ meat) was unchanged in raw meat. The amounts of total saturated, monounsaturated and polyunsaturated fatty acids were significantly increased after frying and roasting. Considering the CLA content in the thermally processed meat, it was shown that roasting is the most favourable process, and the amounts of CLA-isomers in thigh were above 3-fold higher than in breast meat. Thus, CLA-enriched chicken roasted thigh seems to be the valuable source of CLA isomers for humans.