Levofloxacin (LVFX, DR-3355) a new synthetic antibacterial agent, was evaluated pharmacokinetic and clinically in the field of obstetrics and gynecology and the following results were obtained. 1. The transport of LVFX into genital tissues (various regions in the uterus, ovary and oviduct) after a single oral administration of 200 mg was found to be good. 2. Sixteen patients with genital infections (endometritis, salpingitis, cervicitis, mastitis) were treated with LVFX at daily doses of 200-300 mg for 5-15 days. The efficacy rate was 100% and no side effect was observed.