Abstract: Response surface methodology was employed to optimize the extraction conditions of procyanidins from Aronia melanocarpa and antibacterial activity was researched by Oxford- cup tests. Results indicated that the optimum extractive conditions were determined as follows: ethanol concentration 62%,liquid to solid ratio 25 ∶ 1 m L / g,extraction temperature72 ℃,extraction time 60 min,the content of procyanidins through this optimized procedure was 3.32%. The content of procyanidins were four times as much purification as crude extracts after the treatment by AB- 8 macroporous resin,which content of procyanidins was 14.29%.Bacteriostatic experiment of procyanidins from black chokeberry on several strains tested showed antimicrobial effect as follows: Bacillus subtilis > Staphylococcus aureus > Escherichia coli > Saccharomyces cerevisiae.Antibacterial activity increased with increasing of procyanidins concentration and crude extracts of Aronia melanocarpa procyanidins had better antibacterial activity.