The problem of excess fat and cholesterol is considered one of the major challenges facing the health sector because of its serious health complications and being a cause of heart disease and atherosclerosis, which are considered among the main causes of death around the world.Thus, the goal of the study was to find three edible oils that were high in unsaturated fatty acids and sterols—olive oil, sunflower oil, and flaxseed oil—and investigate them in order to see if they could be used to lower the incidence of high blood fats. The steps of the study can be limited to the following points: 1- Determine chemical and physical characteristics of flaxseed, olive and sunflower oils. 2- Determine the fatty acids and sterols content of flaxseed, olive and sunflower oils. 3- Study the effect of feeding of flaxseed, olive, sunflower oils and mixture of the three oils (%10 in diet) on lipid profile, liver function and heart function on rats feeding on hypercholestrolemic diet.