The integrated membrane technology of ultrafiltration(UF) and nanofiltration(NF) were used for purification of the hydrolysate of steam-exploded wheat straw by xylanase with various molecular weight cut-offs (MWCO). The reducing sugar concentrations and color values were collected, and decolorization rates and reducing sugar recovery were obtained. Then, an optimum UF membrane was selected for decolorization. The permeate of UF was concentrated by NF with MWCO 150 Dalton. Decolorization rate reached 63.6% (on color value in feed) and total reducing sugar recovery(on reducing sugar concentration in feed) was 92.1% by integrated membrane technology, which indicate that integrated membrane technology of UF and NF can decolor and concentrate hydrolysate of steam-exploded wheat straw by xylanase. With high membrane flux, the integrated membrane technology may have industry application prospect.