The main goals of the present research were to investigate fatty acid composition and effects of animal fat or vegetable oil supplemented diets on serum, liver and heart inflammatory and oxidative stress markers in healthy rats. 24 male adult albino rats were equally allocated into 4 dietary fat (7% w/w) groups: Corn oil, olive oil, subcutaneous rump fat and Peri-kidney fat diet. The fatty acids types and proportions in vegetable oils and animal fats that could effect on the biochemical markers in this study were investigated using gas chromatography accompanied by mass spectrometric detection. The most abundant fatty acids present in corn oil were linoleic acid (34.42%), oleic acid (25.59%) and palmitic acid (16.21%). The most abundant fatty acids present in olive oil were oleic acid (59.38%), palmitic acid (10.36%) and linoleic acid (8.13%). The most abundant fatty acids present in rump fat were oleic acid (24.74%), stearic acid (22.39%) and palmitic (19.23%). The most abundant fatty acids present in peri-kidney fat were palmitic acid (29.01%), stearic acid (22.92%) and oleic acid (19.92%). Serum inflammatory and tissues oxidative stress markers were significantly increased, however hepatic and cardiac antioxidants activities were significantly decreased in rats received animal fats in particular peri-kidney fat compared to those consumed vegetable oils particularly olive oil. Altogether, the increased oleic acid, coupled with increased antioxidant enzyme activities, decreased saturated fatty acid and serum inflammatory and tissues oxidative stress markers indicated that, olive oil consumption does not pose significant risks on liver or heart of rats.