In this paper, the electroanalysis and spectrophotometry were used to study the antibacterial ability of copper and stainless steel. Took Escherichia coli and luminescent bacteria as examples, the antibacterial effects of stainless steel on bacteria were very weak, but the killing rate of bacteria exposed to metal copper for 30 min was over 90%. The antibacterial ability of copper may be potential application to the field of sanitation disinfection, food packing and the conveyance of drinking water.