Adsorption of xylans extracted from birchwood and oat spelt on Hw-BKP were analyzed using HPLC. The effect of xylan adsorption on paper properties such as tensile, tear index and brightness was also investigated. The constituents of xylan was analyzed with HPLC after hydrolysis with dilute sulfuric acid. It was shown that xylose was the major constituent and small amounts of glucose and galactose were contained in the xylan samples. Adsorption of xylan on hardwood fibers was evaluated using acid hydrolysis and HPLC techniques. Results showed that the adsorption of negatively charged xylan on the fiber surface was negligible probably because electrostatic repulsion between these two materials. Pretreatment of the fiber with alum increased xylan adsorption. The amount of adsorption increased up to 30 mg/g. With the increase of xylan adsorption both tensile and tear strength of the handsheet increased suggesting xylan can be a very effective strength agents for papermaking. Brightness of the handsheets decreased, however, with the use of xylan.