PROBLEM TO BE SOLVED: To provide a preparation for preparing a liquid preparation for oral administration, more excellent in preservation stability and containing a polyethylene glycol, an electrolyte and ascorbic acid as main components.SOLUTION: The oral administration preparation for preparing the liquid preparation for the oral administration by mixing it with water is provided in which the liquid preparation for the oral administration having 30 to 350 g polyethylene glycol content and 3 to 20 g ascorbate content for 1L aqueous solution is prepared by dissolving the preparation in water, and a moisture permeable container housing (a) the polyethylene glycol and (b) a first dry composition containing ≥1 kind of electrolyte selected from sodium chloride, potassium chloride, an alkali metal sulfate and an alkaline earth metal sulfate, and another moisture permeable container housing (c) a second dry composition containing the ascorbate component selected from the ascorbic acid and ≥1 kind of salt of the ascorbic acid are contained in a water vapor barrier type container.
