Objectives : This study was designed to investigate the effectiveness of adjunctive herbal therapy combined with conventional therapy on antibiotic-associated diarrhea (AAD) treatment. Methods : The medical records of 25 patients admitted to the Intensive Care Unit at Kyunghee Oriental Medical Center between January 1, 2009 and January 30, 2010 were reviewed. The charts were analyzed for the general characteristics, site of infection, predominant bacteria, antibiotic treatment, herbal medicine treatment, effect on liver and kidney functions, and the effect of therapy on diarrheal duration. Results : 48% of the 25 patients were male while 52% were female. The average age was 67.2 years old. The most commonly used antibiotic was fluoroquinolone (40.0%) and the most commonly used herbal medicine was Samchulkunbi-tang (24.0%). The average diarrheal duration was 8.9 days. No significant change in hepatic and renal function was discovered before and after treatment with herbal medicine. Conclusions : The results suggest that herbal therapy would be a safe and effective treatment for AAD. Further study investigating the usage of herbal medicine in AAD treatment is anticipated.