NOVELTY - Preparing high ester catechin tea polyphenol comprises: (a) extracting tea leaves to obtain a tea extract, performing rough filtration and ceramic membrane microfiltration, and concentrating in a reverse osmosis membrane to obtain a tea polyphenol membrane concentrated solution; and (b) packing styrene-type polar resin into a chromatographic column, washing the column, balancing column bed speed, loading the membrane concentrated solution, taking a mixed solution of edible alcohol and deionized water as an eluent, eluting, performing vacuum evaporation, concentrating and drying.    USE - The method is useful for preparing high ester catechin tea polyphenol.    ADVANTAGE - The method: does not utilize any conventional processes e.g. use of metal ion precipitating agent, ethyl acetate, chloroform, acetone, methylene dichloride and other toxic solvents in the whole process; obtains a safe and highly pure tea polyphenol product; and efficiently improves total catechin content of the product with high biological activity of ester catechin content; and is ecofriendly.    DETAILED DESCRIPTION - Preparing high ester catechin tea polyphenol comprises: (a) extracting tea leaves with deionized water at 80-90 degrees C, where solid-liquid ratio is 1:8-1:15, extracting 1-3 times for 30-50 minutes per extraction technique parameter to obtain a tea extract, performing rough filtration through a 200-400 mesh filter cloth, performing ceramic membrane microfiltration with 0.2-0.5 mu membrane aperture and concentrating in a reverse osmosis membrane to obtain a tea polyphenol membrane concentrated solution; and (b) packing styrene-type polar resin having grain diameter of 0.50-0.75 mm greater than or equal to 90%, specific surface area of greater than or equal to 330 m2/g, wet-bulk density of 0.65- 0.70 g/ml into a chromatographic column, washing the column with edible ethanol solution (95%), balancing chromatography column bed speed to 1.5-2.5 bed volume/hour with a specific amount of deionized water, loading the tea polyphenol membrane concentrated solution into the column bed, taking a mixed solution of edible alcohol and deionized water with 8:2-9:1 volume ratio as an eluent, eluting at 1.5-2.5 bed volume/hour elution speed, performing vacuum evaporation on the obtained eluate, concentrating and drying.