In Cho Ray Hospital, infection is a serious problem, especially in patients with chemotherapy. Aim: To assess the predictive power of infection probability score to the onset of healthcare-associated infections in hematology-oncology patients. Method: A retrospective surveillance survey. Results and conclusions: During 3 months from May 1st, 2011 to July 31st, 2011, we researched 34 patients admitted to Hematology Department of Cho Ray Hospital.