Abstract The conversion of the biomass into high value‐added chemicals is an attractive topic in green chemistry. In this work, we studied the synthesis of 2,6‐deoxyfructosazine (2,6‐DOF) and 2,5‐deoxyfructosazine (2,5‐DOF) from cellobiose and inulin, respectively, in aqueous solution by an one‐pot two‐step route. In this method, cellobiose or inulin was first hydrolyzed into glucose or fructose and then reacted directly with ammonium formate to form 2,6‐DOF or 2,5‐DOF. The effects of reaction temperature, reaction time, pH value on the yields of the products were studied. It was demonstrated that the cellobiose and inulin could be converted to 2,6‐DOF and 2,5‐DOF effectively at optimized condition.