Abstract: ［Abstract］Objective　To learn the influencing factors of the time of using antibiotics for treating bacterial ventilator associated pneumonia．Methods　We selected the patients with bacterial ventilator associated pneumoniain who admitted in ICU from January 2011 to December 2014 . Then we investigated the possible factors influencing the time of using antibiotics，such as demographic characteristics，APECHII score，the plan of treatment , the situation of Prevention and control，etc. Results　The appearance of multiple drug-resistant bacteria, positive sputum culture，higher score of APECHII and tracheotomy extended the time of using antibiotics, while using the antibiotics with allicin shortened the time of using antibiotics. Tracheotomy was the most influencing factors of the time of using the antibiotics，while APECHII score was the less influencing factors. Conclusion　Rational use of antibiotics and combined antibiotics with allicin is beneficial to treat the bacterial ventilator associated pneumonia, and improve the level of critically patients.