Two antibiotics recommended by the guideline of Infectious Diseases Society of America (IDSA) were selected for treatment of febrile neutropenia, and these paired antibiotics were changed periodically three times. The clinical efficacy of each antibiotic was retrospectively evaluated at the end of the final period. There was no significant difference about efficacy rate between two kinds of antibiotics in the same sequential period. However, the efficacy rate has been rising and febrile duration has been shortening by degrees. Only a few drug resistant bacteria were recognized by the surveillance culture during antibiotic cycling. Recently, antibiotic cycling therapy has attracted attention especially in the ICU. However, a clinical study of treatment for febrile neutropenia has not been reported. Our trial suggests that cycling therapy may be useful for febrile neutropenia. However, Some deviation in the patients characteristics of each period may affect the result. It seems that further examination is necessary about usefullness of the cycling therapy for febrile neutropenia.