The invention discloses a method for separation purification of walnut green seedcase polyphenol substances by macroporous resin. The method comprises 1, carrying out extraction on walnut green seedcase dry powder at a temperature of 35-40 DEG C through ethanol with content of 50% under ultrasonic action many times, carrying out vacuum filtration on the extract, evaporating the filtrate to obtain walnut green seedcase polyphenol crude extract, diluting the walnut green seedcase polyphenol crude extract until a desired concentration is obtained, and carrying out refrigeration for next use, 2, determining total polyphenol content of walnut green seedcase by a Folin-Ciocaileu method, 3, carrying out macroporous resin pretreatment, 4, carrying out macroporous resin static adsorption and desorption, 5, carrying out macroporous resin dynamic adsorption and desorption, and 6, through a HPLC method, determining free phenol content and composition of the walnut green seedcase polyphenol extract obtained by the macroporous resin separation purification so that the whole separation purification process is finished. The method provides the novel approach for separation purification of walnut green seedcase polyphenol substances, can be operated simply and realizes high separation purification quality and efficiency.