Asian ginseng (Panax ginseng C.A. Meyer), American ginseng (Panax quinquefolius) and notoginseng (Panax notoginseng) are the three most commonly used ginseng botanicals in the world. With the increasing interests on antimicrobial properties of plants, the antimicrobial activities of ginseng species have been investigated by a number of researchers worldwide. This overview interprets our present knowledge of the antimicrobial activities of the three ginseng species and some of their bioactive components against pathogenic bacteria (Pseudomonas aeruginosa, Helicobacter pylori, Staphylococcus aureus, Escherichia coli, Propionibacterium acnes, et al.) and fungi (Candida albicans, Fusarium oxysporum, et al). Ginsenosides, polysaccharides, essential oil, proteins, and panaxytriol are all might responsible for the antimicrobial activities of ginseng. The antimicrobial mechanisms of ginseng components could be summarized to the following points: (a) inhibit the microbial motility and quorum‐sensing ability; (b) affect the formation of biofilms and destroy the mature biofilms, which can weaken the infection ability of the microbes; (c) perturb membrane lipid bilayers, thus causing the formation of pores, leakages of cell constituents and eventually cell death; (d) stimulate of the immune system and attenuate microbes induced apoptosis, inflammation, and DNA damages, which can protect or help the host fight against microbial infections; and (e) inhibit the efflux of antibiotics that can descend the drug resistance of the microbial. The collected information might facilitate and guide further studies needed to optimize the use of ginseng and their components to improve microbial food safety and prevent or treat animal and human infections.