目的　探讨医院内获得性肺炎危险因素。方法　对 77例肿瘤患者院内获得性肺炎的危险因素进行 1:1病例对照研究。结果　肿瘤患者院内获得性肺炎 (NP)感染病死率为 14 3 %。发生医院感染危险因素为免疫抑制治疗、手术、住院时间、抗生素应用时间、呼吸道插管。结论　肿瘤患者院内获得性肺炎的发生是多因素综合作用的结果 ,应引起临床重视 ,尽可能控制该感染的发生 Objective To explore the risk factors of hospital acquired pneumonia. Methods A case-control study of risk factors of nosocomial pneumonia in 77 patients with cancer was conducted. Results The mortality of nosocomial pneumonia (NP) in cancer patients was 14 3%. Risk factors for nosocomial infections were immunosuppressive therapy, surgery, length of stay, duration of antibiotic use, and intubation of the respiratory tract. Conclusion The occurrence of nosocomial pneumonia in patients with cancer is the result of multifactorial combined action, which should cause clinical importance and control the occurrence of the infection as much as possible