A certain amount of glucosefructose, sucrose and inulin are still exist in the solution of fructo-oligosaccharide which is obtained by hydrolysis of inulin. Fos solution was purified by the membrane separation process and macroporpus resin. The purification effect for Fructo-oligosaccharide of four kinds of resins (CSR-1Na, CSR-2Na, CSR-3Na, CSR-1Ca) was compared,the optimum was CSR-1Na. The effects of filtration pressure, circulation flow rate, pH on the transmittance of sugars and the permeation flux were studied. The optimum conditions for ultrafiltration were filtration pressure of 10 bar, pH of 6.0, circulation flow rate of 2 L/min, twice and the transmissivity ratio of FOS was 93.7%, the permeation flux was 10.8 L/(m²?SymbolWC@h), the purity of glucosefructose was 63.84%. The optimum conditions for purification of macroporpus resin were temperature of 60 ℃, volumetric flow rate of 1.5 mL/min, pH of 6.0～6.5 and the type of 95 fructooligosaccharides recovery rate was 83.26%.