Multidrug resistant (MDR) bacteria have emerged as a major clinical challenge. The unavailability of effective antibiotics has necessitated the use of emerging nanoparticles as alternatives. In this work, we have developed carbohydrate-coated bimetallic nanoparticles (Au-AgNP, 30–40 nm diameter) that are nontoxic toward mammalian cells yet highly effective against MDR strains as compared to their monometallic counterparts (Ag-NP, Au-NP). The Au-AgNP is much more effective against Gram-negative MDR Escherichia coli and Enterobacter cloacae when compared to most of the potent antibiotics. We demonstrate that in vivo, Au-AgNP is at least 11000 times more effective than Gentamicin in eliminating MDR Methicillin Resistant Staphylococcus aureus (MRSA) infecting mice skin wounds. Au-AgNP is able to heal and regenerate infected wounds faster and in scar-free manner. In vivo results show that this Au-AgNP is very effective antibacterial agent against MDR strains and does not produce adverse toxicity. We conclude that this bimetallic nanoparticle can be safe in complete skin regeneration in bacteria infected wounds.