PROBLEM TO BE SOLVED: To provide a fat emulsion which has improved stability of prostaglandin, excellent transparency, excellent emulsion stability, and long storage life.SOLUTION: A fat emulsion includes a prostaglandin, an oil component, lecithin, and water, wherein the content of lecithin is 500-5,000 times the mass of the content of the prostaglandin, and is 0.5-10 times the mass of the content of the oil component. This fat emulsion containing prostaglandin also includes a higher fatty acid in an amount of 0.06 times or less the mass of the content of lecithin.