The invention relates to an affinity and purification method of endo-xylanase, which belongs to biological technical field. The method of the invention comprises following steps: firstly, connecting aminobenzenesulfonic acid and L-tryptophan to foundation chromatography medium through trichloro triazine activation to prepare affinity separation materials, secondly, enabling cellulose enzyme crudeproducts to be contacted with the affinity separation materials, combining the endo-xylanase on the affinity separation materials, washing out substances which are not combined, then using eluting buffer solution to elute the endo-xylanase from a column specifically, and obtaining the endo-xylanase. The method of the invention can produce the endo-xylanase with high purity, high efficiency, low cost and large scale.