In the research study, there were assessed some selected anatomical and morphological features of male and female pheasants (Phasianus colchicus) from a wildlife population in the region of the Lublin Upland. The pheasants were acquired during hunts in hunting areas in November 2017, where no reintroduction of this species was carried out. Thirty birds were utilized in the research study, of which 10 were females recruited at a game breeding centre and 20 males were acquired in hunting districts leased by hunting clubs. The carcasses were eviscerated, weighed and the breast muscle (m. pectoralis) of the birds was dissected. In the muscle, there were determined the fat content and the fatty acid profile as were the atherogenic (AI) and thrombogenic (TI) index and the ratio of hypocholesterolemic/hypercholesterolemic acids. A marked sexual dimorphism was shown in the body weight and thus in the carcass weight in favour of the males. In the case of young birds, the difference was 274.3 g and in the case of the adults – 392.2 g. Also, as for the hens, the weight of all their internal organs classified as  offals was significantly lower. The adult hens were characterised by the lowest slaughter efficiency equalling 70.5  %, whereas the young hens by the highest equalling 74.2 %. The slaughterhouse performance indicators obtained  were similar to those obtained for the pheasants bred in poultry farms; small deviations were conditioned by the age and origin of the birds. The profile of fatty acid in the fat of pheasants was determined more by the age of  birds than by their sex. The most beneficial composition of fatty acids and the most beneficial atheroand  thrombogenic indices were found in the fat in pectoral muscles of one-year-old pheasants.