Abstract: The present invention discloses a method for isolating and purifying anhydrogalactose. Using the method for isolating and purifying anhydrogalactose including the steps of preparing a sugar mixture containing anhydrogalactose produced through chemical synthesis and hydrolysis; and isolating anhydrogalactose by performing recycling preparative liquid chromatography (recycling-prep-LC) with the sugar mixture, highly pure anhydrogalactose can be efficiently isolated and purified in large amounts.