NOVELTY - Separating and purifying andrographolide comprises taking herba andrographitis extract, adding 25-35 ml or 95 vol.% of alcohol with 1 g of herba andrographitis extract, heating and stirring to dissolve the herba andrographitis extract into dissolved solution at a heating temperature of 55-65 degrees C, adding 90-100 meshes in an active carbon with 1.5-2.5 wt.% of the herba andrographitis extract to remove impurities of the dissolved solution, and ceaselessly stirring the impurities removed dissolved solution at a temperature of 55-65 degrees C for 1-2 hours.    USE - The method is useful for separating and purifying andrographolide, which is useful for treating acute dysentery, acute gastroenteritis, upper respiratory tract infection and acute tonsil inflammation.    ADVANTAGE - The method provides an andrographolide without toxicity in an environmentally-friendly and safe manner.    DETAILED DESCRIPTION - Separating and purifying andrographolide comprises taking herba andrographitis extract, adding 25-35 ml or 95 vol.% of alcohol with 1 g of herba andrographitis extract, heating and stirring to dissolve the herba andrographitis extract into dissolved solution at a heating temperature of 55-65 degrees C, adding 90-100 meshes in an active carbon with 1.5-2.5 wt.% of the herba andrographitis extract to remove impurities of the dissolved solution, ceaselessly stirring the impurities removed dissolved solution at a temperature of 55-65 degrees C for 1-2 hours, filtering the stirred solution using a titanium rod filter to remove the active carbon, collecting a filtrate in an upper column by performing a column exchange adsorption to obtain a column padding material such as macro reticular resin or silica gel, eluting the macro reticular resin or silica gel using pure water until obtaining clear effluent, adding 90 vol.% of alcohol with 1.5-2.5 times of an eluted product, performing silica gel thin-layer chromatography process comparing an andrographolide with a new andrographolide standard substance to determine an initial point of collecting eluent in the eluting process, placing a sample on the silica gel thin-layer plate using thin-layer and methanol in a volume ratio of 1:2, as a developing solvent, pouring the solvent into iodine vapor, collecting an eluent containing rich andrographolides and new andrographolide according to a silica gel thin-layer chromatography result, concentrating the eluent till initial volume of 45-55% under a vacuum pressure of 0.06-0.08 MPa at a temperature of 45-55 degrees C is achieved, stewing the concentrated solution, naturally cooling to crystallize, leaching to obtain a crystal, adding 25-35 ml of alcohol in 1 g of crystal A, heating and dissolving the crystal to obtain a dissolved solution at a temperature of 55-65 degrees C, concentrating the dissolved solution till initial volume of 60-70% under a vacuum pressure of 0.06-0.08 MPa at a temperature of 45-55 degrees C, stewing the dissolved solution, cooling to crystallize, and leaching to obtain a columnar crystal. A weight content of a herba andrographitis total lactone in the herba andrographitis extract is more than 50%.    DESCRIPTION OF DRAWING(S) - The figure shows a flow diagram of a method for separating and purifying andrographolide.