The purpose of the study was to investigate the lipid peroxidation and antioxidant status as well as biochemical profile in sheep naturally infected with Dicrocoelium dendriticum and hydatid cysts. Ten sheep naturally infected with D. dendriticum, 10 sheep naturally infected with hydatid cysts, and 10 healthy sheep were used. The blood and visceral organs of sheep brought to a slaughterhouse in the region of Kırıkkale were checked for D. dendriticum and hydatid cysts. Plasma total protein, albumin, total bilirubin, total cholesterol, Ca, Mg, inorganic P, Cu, Zn, vitamin A, vitamin C, vitamin E, ß-carotene, AST, ALT, GGT, ALP, erythrocyte MDA levels, and SOD and CAT activities were detected. Erythrocyte MDA, plasma total bilirubin levels, and AST and ALP activities were increased while total protein and vitamin A levels were decreased in sheep infected with parasites. Erythrocyte SOD activities were decreased in D. dendriticum group, and CAT activities were decreased in the hydatid cyst group and D. dendriticum group. Total bilirubin levels were increased and total protein levels were decreased in sheep infected with parasites. These results suggest that endoparasitic infections such as D. dendriticum and hydatid cysts cause oxidative stress and change some biochemical parameters in sheep.