Abstract: The present invention provides(1) a method for preparing lipid powder for use in the preparing liposome, which comprises supplying at a constant speed an organic solvent solution of lipids having liposome membrane forming ability to a tubular heater heated externally, evaporating the organic solvent in the heater to prepare a mixture substantially of solids and organic solvent vapor and introducing this mixture at a high speed into a vacuum chamber of not more than 300 mm Hg, to volatilize the organic solvent instantaneously and dry the solids, and(2) a method for preparing liposomes comprising dispersing the lipid powder obtained by the above method (1) into an aqueous solvent.