Extracting method of D-xylose and L-arabinose

The invention provides an extracting process of D-xylose and L-arabinose. The extracting process comprises the following steps of: acidizing forestry and agricultural residues, carrying out steam explosion on the acidized forestry and agricultural residues to obtain the forestry and agricultural residues subjected to steam explosion, and finally carrying out aqueous extraction, separation and crystallization to obtain the D-xylose and L-arabinose. According to the technical scheme of the invention, the extracting method has the following advantages that an acid solution is recycled, and therefore the acid consumption is reduced; as the acid in an extracting solution is low in content, the load of a later-peroid purifying treatment is lightened; the peroid is short, continuous steam explosion production can be achieved, and the equipment investment is reduced when the capacity is unchanged; steam is not heated together with the acid solution in the boosting process, so that the steam consumption is greatly reduced, and energy sources are saved; and as the process of separating the D-xylose and the L-arabinose first and then respectively crystallizing is adopted, the purity of massecuite during crystallization of the D-xylose is improved, and the quality and crystallization yield of the D-xylose are improved.