Objective To investigate the risk factors of ventilator associated pneumonia infection in basement colligation ICU and summarize strategies, to reduce VAP incidence rate, shorten hospital day, cut down medicai fees and death rate. Methods Retrospect the clinical data of 36 machine ventilation Patients happen to VAP, and rsearch the questionnaire. Results The reason of VAP was versatility, for instance machine ventilation, patient and medical staff, inasivenes operation, using antiacid, sickroom surroundings, and so on. Conclusion To shorten machine ventilation time as far as possible profit reducing VAP incidence rate. The criticality of shortening machine ventilation is strengthening protective measure. The best strategy is taking composite prevention and cure.