Abstract： To observe the relationship between different pathogens and mechanical ventilation time in patients with ventilator-associated pneumonia. Methods A retrospective study was per-formed on 91 cases with ventilator-associated pneumonia who were admitted between January 2008 and July 2017. The patients were divided into G+ bacterial group,G- bacterial group and bacterial + fungal group according to the results of sputum culture. There were 24 patients in the G+ group,including 11 males and 13 females,(49. 87 ± 7. 59)years old,ranging from 39 to 65 years old;24 patients(17 males and 15 fe-males)in the G- group were(49. 18 ± 8. 77)years old,ranging from 37 to 66 years old. And 35 patients in the bacterial + fungal group,including 19 males and 16 females,(50. 97 ± 6. 53) years old,ranging from 34 to 67 years old. The blood routine,blood biochemistry,coagulation tests and procalcitonin were collected before the positive results of sputum culture. The differences of ventilator evacuation in each group compared by Kaplan-Meier survival analysis. Results The platelet(PLT)in G+ bacterial group [(171. 75 ±51. 28)×109/L] increased significantly than G- bacterial group [(121. 40 ± 44. 78)×109/L] and bacterial + fungal group [(102. 51 ±36. 42)×109/L,P<0. 05] ,the PLT between G- bacterial group and bacterial + fungal group has no statistical difference( P>0. 05). The albumin(ALB) between G+ bacterial group and G- bacteria group has no statistical difference(P>0. 05),the ALB in bacterial + fungal group [(25. 42 ± 2. 10)g/L] dropped significantly than G+ bacterial group [(27. 62 ± 1. 88) g/L] and G- bacterial group [(26. 78 ± 2. 19)g/L,P<0. 05]. The D-dimer(D-D)between G+ bacterial group and G-bacteria group has no statis-tical difference(P>0. 05),the D-D in bacterial + fungal group [(11. 94 ± 5. 79)mg/L] increased signif-icantly than G+ bacterial group [(7. 08 ± 3. 21)mg/L] and G-bacterial group [(9. 09 ± 3. 99)mg/L,P<0. 05]. The procalcitonin(PCT)in G+ bacterial group and the G-bacterial group were higher than the bac-terial + fungal group,but the difference were not statistically significant (P>0. 05). The time of ventilator use in the bacterial + fungal group [(30. 42 ± 5. 53) d] was higher than the G+ bacterial [(26. 66 ± 4. 97)d] and G- bacterial group [(21. 40 ± 4. 72) d,P<0. 05],and the G+ bacterial group was higher than the G- bacterial group(P<0. 05). Kaplan-Meier survival analysis showed that there were statistically significant differences between G+ bacteria group,G- bacteria group and bacterial + fungal group in me-chanical ventilation time(P<0. 05). Conclusion The infection process of ventilator-associated pneumonia was accompanied with thrombocytopenia and the activation of coagulation,fibrinolysis system. Fungal infec-tions can prolong the use of respirators. Therefore,it is important to avoid the super infection of fungi while controlling the bacterial infection.