The aim of the study was to determine the influence of the addition for 6 weeks of 12 ppm lycopene (Lyc), 2% fish oil (FO) or 0.25 ppm Se as selenate (Sevi) or selenized yeast (SeY) to an isoenergetic and isonitrogenous ration containing sunflower oil as the source of energy on the profile of fatty acids (FA) and the oxidative stress in thigh muscles of female and male chickens. The ration with FO most efficiently increased the concentration of saturated fatty acids (SFA), atherogenic SFA and thrombogenic SFA as well as the concentration sum of all assayed FA in muscles of chickens. the rations with lyc, sevi or SeY revealed negligible and inconsistent impact on the concentration of individual SFA in muscles compared with the control. The ration with FO most efficiently increased the concentration of polyunsaturated FA (PUFA), especially