Neutropenia is very common in patients received hematopoietic stem cell transplantation, with median duration of about 14 days. Almost all neutropenia will suffer from febrile without prophylactic antibiotics. IDSA recommended fluoroquinolones as prophylaxis in neutropenia patients of high risks, while in China, major pathogens possess high resistance to fluoroquinolones. It is not clear whether prophylaxis is of benefit, nor the appropriate prophylaxis regimen.