The purpose of this study was to assess the effects of added Sunflower Emulsified Oil (SEO) as fat replacer in preparing low fat beef burger by substitution of fat at the ratio of 5, 7.5 and 10 % respectively. Gross chemical composition, physical properties, cooking characteristics namely Texture Profile Analysis (TPA), shrinkage, cooking loss and Biological evaluation were made. Addition of Sunflower Emulsified Oil (SEO) increased the moisture, protein, carbohydrates and decreased ether extract, ash, shrinkage and cooking loss in compare with control beef burger sample. Significant differences were observed in TPA for beef burger. In low fat beef burger prepared with SEO, Total cholesterol (TC), Triglycerides (TG), HDL-C and LDL-C reached 78.47, 174.73, 33.53 and 9.99 mg/dl respectively compared with positive control group 98.37, 224.50, 17.80 and 35.67 mg/dl respectively. In conclusion, Sunflower Emulsified Oil (SEO) is effective in improving chemical, physical and functional properties of beef burger and also, had a hypolipidemic effect on experimental rats.