Objective To study the significance of the prognosis assessment by acute physiology and chronic health evaluation (APACHE Ⅱ ),sequential organ failure assessment (SOFA) score,clinical pulmonary infection score(CPIS) and multiple organ dysfunction syndrome (MODS) score in the patients of ventilator-associated pneumonia (VAP). Methods The clinical data of 68 cases with VAP in the ICU or RICU were studied. APACHE Ⅱ , SOFA and MODS scores on admission and APACHE Ⅱ , SOFA, CPIS and MODS scores on the first 24-hour of VAP diagnosis were recorded. The area under the receiver operating characteristic curve(AUROC ) and Logistic regression were used to estimate the prognostic ability by the four kinds of scoring systems. Results The APACHE Ⅱ , CPIS, MODS and SOFA scores on the first 24-hour of VAP diagnosis were significantly higher in non-survivors than those in survivors. AUROC of APACHE Ⅱ ,SOFA,MODS and CPIS respectively were 0.80,0.75,0.73,0.71. Logistic regression analysis showed that only APACHE Ⅱ＞ 18 scores on the first 24-hour of VAP diagnosis was an independent predictor of the mortality (OR: 5.7,95% CI: 1.9 - 20.0, P = 0.013). Conclusion The APACHE Ⅱ on the first 24-hour of VAP diagnosis may be a useful index in predicting progress of patients with VAP.