The invention provides an amino sugar modified antibacterial gold nanoparticle and a preparation method thereof, and applications. The prepared antibacterial gold nanoparticle has an excellent antibacterial property, and can resist multidrug resistant bacteria; and the antibacterial gold nanoparticle is good in biocompatibility and low in toxicity to body cells. The antibacterial gold nanoparticlecan be used for clinical wound management, operations to prevent organs from adhering, beauty treatment, and various wound infections such as burn, scald and bedsore infections, so that the antibacterial gold nanoparticle is an extremely excellent medical antibacterial material.