Since the ancient times the therapeutic application of honeybee venom (BV) is practised and persisted until the present days. Resistant bacteria are in emergence and some drugs no longer have an antimicrobial action. To purify the melittin known as antibacterial peptide, five major peptidergic subfractions were separated, purified and identified from the whole BV. We investigated the antibacterial activity of whole BV and purified melittin against Staphylococcus aureus by the minimum inhibitory concentrations (MIC) and the postantibiotic effect (PAE). The MIC of whole BV for S. aureus was 0.06 ㎍/㎖, respectively. The MIC of melittin was 0.06 ㎍/㎖ on S. aureus. The in vitro PAE of whole BV and isolated melittin were determined using E. coli and S. aureus. The PAE of whole BV against S. aureus were 3.45 h (1×MIC). The PAE of melittin against S. aureus was 4.35 h (1 × MIC). Also both whole BV and melittin killed S. aureus at 5 × MIC. The regrowth wasn't observed after 18 h. These results suggest that whole BV and melittin will be developed a novel antibacterial drug.