Infectious complications during neutropenic periods are major causes of morbidity and mortality especially for patients with hematological diseases, and prompt initiation of antibiotic therapy is warranted for those who develop febrile neutropenia. As for initial therapeutic agents, beta-lactam antibiotics, i.e., third- or fourth-generation cephalosporins and carbapenems have been used frequently because of their strong and broad-spectrum of action. However, under these conditions, development of resistance mediated by a beta-lactamase is concerned, and there is a need for alternative non-beta-lactam antibiotics for this indication. Ciprofloxacin is a potent agent covering against wide range of strains including Pseudomonas aeruginosa, and expected as a potential candidate. We have therefore planned a prospective randomized controlled trial designed to compare intravenous ciprofloxacin with cefepime for febrile neutropenic patients.