Accurately weighed azide fully acetylated galactose (0.7466g, 2mmol) in a roundness flask containing 100mL of methanol, added CH3ONa (432.1mg, 8mmol), nitrogen protection, stirring at room temperature for 2h, TLC detection of the reaction was complete, the system pH was adjusted to 7 with an ion-exchange resin, filtration, concentration under reduced pressure, to obtain the yellow liquid compound 1- azido-1-deoxy--D-galactopyranoside, the reaction was completed. The yellow liquid compound 1-azido-1-deoxy--D-galactoside was obtained.