Abstract: A method for preparing n-acetylglucosamine starting from glucosamine base having a purity level of at least about 99 wt. % and a maximum halide content of about 0.01 wt %. The glucosamine base is slurried in a diluent comprising a C1-C4 straight or branched-chain alcohol, e.g., isopropyl alcohol, sec. butyl alcohol, tert. butyl alcohol, etc. Thereafter, an acylating agent, e.g., acetic anhydride, present in at least a stoichiometric amount, is slowly added to the slurry while maintaining the reaction mixture at a temperature below about 20° C. The n-acetylglucosamine prepared by the process of the invention will be quite pure, e.g., it will have a purity of at least 98%, as measured by HPLC, a melting point in the range of 196-205° C. and a specific rotation, measured at room temperature after standing in water for several hours, of [?]D=39-43°.