The lipid profile (total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides) is used as part of a cardiacdisease risk assessment. In this research, we investigate the efficiency of Fishoil to decrease the levels of total cholesterol and proteins in Wister rats (n =60) weighing (225-250 g). Fish oil was fed for seven weeks to Wister rats. Hematological and physiological parameters were examined by automatic analyzer and the results were statistically analyzed by SPSS.12. In comparison to control rats showed highly significant decrease in values of following physiological parameters; triglycerides, total cholesterol, low density lipoprotein cholesterol, total protein. In contrast, marked increasing in the value of high density lipoprotein cholesterol. These findings indicate that diets containing Fish oil significantly improved the physiological parameters of rats. We suggest that Fish oil as part of food might improve blood parameters and increase high density lipoprotein cholesterol in rats. We further suggest that Fish oil supplementation act as antioxidant agents, and an excellent adjuvant therapy for rats.