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 crude products 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.