PURPOSE: To prevent the destruction of liposome caused by the attack with the phospholipase in the living body, and to enable the selective and concentrated transfer of drug to the aimed organ, by covering the surface of a liposome membrane with an ester of polysaccharide and fatty acid.

CONSTITUTION: The surface of a single-layered or multi-layered liposome membrane composed of only a lipid (e.g. phosphatidylcholine) or of lipid and sterol, is coated with the ester of a polysaccharide (e.g. dextran, amylopectine, pullulan, chitosan, etc.) and fatty acid (e.g. lauric acid, myristic acid, palmitic acid, stearic acid, etc.). The coating can be carried out by adding an aqueous solution containing said ester to an aqueous solution containing liposome, and stirring the mixture.