Burn wound is suitable site for incidence of resistant infections. Thus, the research for finding effective drugs against this problem is necessary. Medicinal herbs with antimicrobial activity have important role in traditional medicine. The purpose of this study was to determine antibacterial activity of methanolic extract of Terminalia catappa L. fruit against bacteria isolated from burn wound infections and to compare with effects of some selected antibiotics.First, a sample of methanolic extract of the Terminalia catappa fruit was prepared and then its antibacterial activity against 8 bacteria from 100 samples of burn wound infection were evaluated by well diffusion method at concentration of 40 mg/ml and then Agar Serial Dilution method in the range of 0.039-20mg/ml. Also, the MIC (Minimal Inhibitory Concentration) of extract was determined. The antibacterial activity of selective antibiotics was tested by disk diffusion method. The onava test was used to compare the results. The results from the antibacterial tests demonstrated that the Terminalia catappa methanolic extract had been effected against all of Pseudomonas aeruginosa, Acinetobacter spp. and more than 80% of Staphylococcus aureus/epidermidis/saprophyticus, and against 50% of Escherichia coli. The MIC of the extract against all the sensitive cases was 20 mg/ml. The bacteria were often resistant to selective drugs .There was significant difference between the effects of plant and antibiotics on Pseudomonas aeruginosa (P<0.001), Acinetobacter spp. (P<0.05) and Staphylococcus cases (P<0.05). This study demonstrated that methanolic extract of Terminalia catappa have excellent antibacterial activity against most of bacteria isolated from burn wound infections and its effect is better than selective antibiotics. However, we need more in vitro and in vivo investigation.