Objectives : This experimental study was performed to investigate the antibacterial effect of Caesalpinia sappan and Coptis chinensis extract against B. cereus and V. parahaemolyticus. Methods : Methanol extracts of C. sappan and C. chinensis was tested against B. cereus and V. parahaemolyticus by paper disc method. Results : The growth of B. cereus and V. parahaemolyticus was inhibited by C. sappan and C. chinensis extract among 6 kinds of medicinal plant extracts. The extract of C. sappan and C. chinensis extract inhibited the growth of V. parahaemolyticus and B. cereus, respectively. The growth of B. cereus and V. parahaemolyticus had a tendency to increase depend on the concentration of the extract. EtOEt and EtOAc fractions and EtOEt and BuOH fractions of the C. sappan extract had a high antibacterial activity against B. cereus and V. parahaemolyticus, respectively. And, BuOH and $H_2O$ fractions of the C. chinensis extract showed antibacterial activity against B. cereus highly. Conclusions : C. sappan and C. chinensis extract efficiently inhibited the growth of B. cereus and V. parahaemolyticus.