Background: Milkfish (Chanos chanos Forsk) contains various kinds of fatty acids which can lower cholesterol levels and an emulsion is made from milkfish oil because fish oil is easier to prepare as an emulsion. This study aimed see the best and stable formula in the stability test and to determine the activity of milkfish oil emulsion as a lowering cholesterol. Method: Emulsion physical evaluation test. Cholesterol levels were measured using an experimental design method and divided into 5 groups, namely: the normal group, the placebo group, the simvastatin group, the milkfish oil group (1mg/200gBB/day) and the milkfish oil emulsion group (1 mg/200gBB/day). Induction of cholesterol in rats using quail egg yolk (10 ml/kgBB). Results: This study made 3 emulsion formulas, each formula distinguished by the number of emulsifier variations between tween 20 and span 80 A (5:5), B (7.5:2.5) and C (10:1). The best formula is seen from the results of the emulsion physical evaluation test. Measuring cholesterol levels using the Tukey HSD statistical test and the ANOVA test stated that there was an effect or difference in decrease cholesterol between treatment groups. Conclusion: Of the three formulations, the best milkfish oil emulsion formula was Formula 1 and milkfish oil emulsion did not have cholesterol lowering activity.