Objective: Studies on separation and purification of gallic acid from Galla chinensis by different resins. Methods: The research compared the absorption capacity and desorbtion effect with different concentration of alcohol of 11 kinds of resins: NKA-2, LS303, HZ816, HP-20, XAD-16, HPD700, HPD500, S-8, AB-8, D101, D301, and the best processing parameters were optimized based on the adsorption and desorption results. Results: NKA-2 was the best one. An optimum purification parameter with sample concentration 7 mg/mL, sample volume 7 BV, flow rate 2 BV/h, elution ethanol concentration 70%, eluti...