The objective of this study was to investigate the antiproliferative activity and apoptosis-inducing mechanism of Concanavalin A (ConA) on human melanoma A375 cells. We firstly simulated the three-dimensional structure of ConA. Subsequently, we found that ConA possessed remarkable antiproliferative effect on A375 cells. Further experimental data indicated that there was a link between its hemagglutinating activity, mannose-binding activity and antiproliferative activity. In addition, we showed that ConA induced A375 cell apoptosis in a caspase-dependent manner. Then, we demonstrated that the treatment of ConA caused mitochondrial transmembrane potential (MMP) collapse, cytochrome c release and caspase activation. In conclusion, we report for the first time that there may be a close correlation between carbohydrate-binding activity of ConA and its antiproliferative activity. Also, we demonstrate firstly that ConA induces A375 cell death in a caspase-dependent manner as well as through a mitochondrial apoptotic pathway.