We present a prospective method of surveillance of health care-associated infection in hematology-oncology inpatients with neutropenia. Incidence rates were calculated on the basis of the number of hospitalized patients, the duration of hospital stay (in days), the number of days of neutropenia, and (in cases of central line-associated blood stream infection) the number of central line-days. We detected 11.4 and 66.4 episodes of febrile neutropenia per 1,000 hospital-days and per 1,000 days of neutropenia, respectively. The incidence of central line-associated blood stream infection was 2.6 per 1,000 central line-days. Gram-negative bacteria were the most prevalent pathogens. Efforts should be made to monitor infection rates on hematology-oncology wards.