NOVELTY - Preparing asiaticoside, comprises (i) carrying out micro-boiling extraction of Centella asiatica thrice, filtering, mixing, carrying out vacuum drying, and concentrating; (ii) placing concentrated solution in a macroporous resin column, carrying out gradient elution by eluting a colorless transparent outflow liquid by adding aqueous solution of 20% ethanol and 75% ethanol, carrying out vacuum drying, concentrating to obtain a thick paste, and dissolving; and (iii) stirring dissolved solution by adding activated carbon, filtering, concentrating, and drying to obtain the product.    USE - The method is useful for preparing asiaticoside.    ADVANTAGE - The method has easy operation procedures; produces high quality product with high yield; and is economical and environmental-friendly.    DETAILED DESCRIPTION - Preparing asiaticoside, comprises (i) carrying out micro-boiling extraction of Centella asiatica thrice in an extracting tank by adding water (20-25 times), filtering each time for 2 hours, mixing the extracted liquid, carrying out vacuum drying, and concentrating to obtain a concentrated solution; (ii) placing the concentrated solution in a macroporous resin column having a length-diameter ratio of 2:1-5:1, then carrying out gradient elution by eluting a colorless transparent outflow liquid, eluting the colorless transparent outflow liquid again by using aqueous solution of 20% ethanol, and eluting by adding 4 column volumes of aqueous solution of 75% ethanol, collecting the aqueous solution of 75% ethanol eluent, carrying out vacuum drying, and concentrating to obtain a thick paste, and dissolving at 75 plus minus 5 degrees C by adding aqueous solution of 95% ethanol (5-8 times) to obtain a dissolved solution; and (iii) adding activated carbon (10%) to the dissolved solution, stirring at room temperature for 30 minutes, filtering when the solution is hot, concentrating the filtrate under reduced pressure, and drying at 80 plus minus 10 degrees C by circulating hot air to obtain the product.