Chitosan is a natural polymer gotten from shrimp and crab skeleton; chemical structure of chitosan is similar to cellulose where hydroxyl (OH) in glucose molecule in cellulose is replaced by amine (ndash;NH2) in chitosan. From the chemical structure and its properties, chitosan can be used as a filler and adhesive to replace the traditional materials and it will improve several properties of papers such as to increase strength, reduce water absorption, increase smoothness, and probably anti bacteria and anti fungus of the papers. The use of chitosan in paper production can also reduce impact on environment, because chitosan is a natural polymer that is degradable. In this research, chitosan will be applied into paper processing to replace filler and also as an adhesive to increase the... properties of the paper. The result shows that low molecular weight chitosan, 1%, can affect the decrease of water absorption property and increase paper strength and the smoothness of the paper.