Bacterial vaginosis (BV) is considered to be one of the most common vaginal infections in women. Fifteen symptomatic women with BV were enrolled in this study. Ten patients with the diagnosis of BV were treated with 10 days oral administration of metronidazole (MTN), 500 mg twice a day, and five patients with cefdinir (CFDN), 300 mg three times a day. In the MTN therapy, the rate of abnormal vaginal discharge subjectively decreased from 100 to 60%, the rate of abnormal vaginal discharges objectively decreased from 100 to 20%, the rate of positive amine tests decreased from 100 to 20%, the rate of genital malodor and abnormal pH of vaginal discharges decreased substantially from 100 to 10%, and the rate of the presence of clue cells also decreased notably from 90 to 10%. However, in the CFDN therapy, none of these factors improved. With respect to susceptibility to CFDN and MTN, CFDN demonstrated good antibacterial activity against almost all bacteria isolated except Gardnerella vaginalis. On the other hand, MTN demonstrated excellent activity against anaerobic bacteria except Peptostreptococcus spp., and had no antibacterial activity against aerobic bacteria. Since the therapeutic effect of MTN in BV appeared to be better than that of CFDN, anaerobes may play a major role in causing clinical symptoms in patients with BV.