Sulbactam/cefoperazone (SBT/CPZ), a new developed antibiotic, was clinically studied. The following results were obtained. Total of 5 cases comprising 1 with endometritis, 3 with Bartholin's abscess, 1 with pyometra (due to corpus cancer) were treated with SBT/CPZ at a dose of 1 g twice daily for 4-5 days by intravenous injection or intravenous drip infusion. The clinical response was good in all cases. A case with pyometra did not respond to the therapy in bacteriologically. Side effects and abnormal laboratory findings due to the drug were not noted.