Abstract: Objective To provide the reference for initial experience-based treatment of Peudomonas aeruginosa-induced hospital acquired pneumonia（HAP） by studying the risk factors for its 30-day mortality. Methods Clinical data about 100 patients with Paeudomonas aeruginosa-induced HAP admitted to ICU in Chinese PLA General Hospital from January 2009 to October 2011 were retrospectively investigated and risk factors for their 30-day mortality were analyzed.Drug sensitivity test was performed for Paeudomonas aeruginosa isolated from the lower respiratory tract. Results High APACHEⅡscore and uncovered pathogens（P=0.01） were the risk factors for 30-day mortality of HAP patients.The resistance rate of Paeudomonas aeruginosa to ceftazidime,ciprofloxacin,cefepime and piperacillin/tazobactam was very low,accounting for 17%,19%,21% and 26%,respectively. Conclusion High APACHEⅡscore and uncovered pathogens are the risk factors for 30-day mortality of HAP patients.The anti-Paeudomonas aeruginosa activity of ceftazidime,ciprofloxacin,cefepime and piperacillin/tazobactam is rather good.