Objective To study the clinical characteristics、risk factors and preventive measures in the patients of hospital-acquired septicemia in ICU.Methods Retrospective survey was carried out in 76 patients with hospital-acquired septicemia from 2002 to 2005.Results The hospital-acquired septicemia was related to the underlying disease、aggressive procedure and long duration of combined antibiotics.The most bacteria were Gram-negative bacilli.Fungemia must be given reconstruction.Conclusions It is important to reduce the aggressive procedures and reasonably use antibiotics in the prevention of the hospital-acquired septicemia for patients.