To study the value of lung ultrasound score (LUS) in assessing the clinical outcome of patients with ventilator-associated pneumonia(VAP). A total of 99 VAP patients were enrolled in a prospective study. All patients met the diagnostic criterion of VAP based on the 2013 guidelines and admitted into our ICU from Jun 2013 to Jun 2015. All parameters were recorded on the diagnostic day (day 1) and day 5, including LUS, clinical pulmonary infection score (CPIS), chest X ray (CXR), Acute Physiology and Chronic Health Evaluation Ⅱ (APACHEⅡ) score, Sequential Organ Failure Assessment(SOFA) score, etc. According to the CPIS, patients were divided into 2 groups(CPIS less than 6 and more or equal to 6). CPIS and LUS were similar on day 1 between two groups (P>0.05). However, on day 5, significant differences of CPIS and LUS were found between groups with CPIS<6 and CPIS≥6 (P=0.019 and P<0.001 respectively). LUS decreased on day 5 in CPIS<6 group and increased in CPIS≥6 group. In CPIS<6 group, there was a positive correlation between LUS and CPIS on day 1(r=0.375, P=0.003) and day 5 (r=0.590, P<0.001). CPIS≥6 groupshowed the same trend on day 1 (r=0.484, P=0.002) and day 5 (r=0.407, P=0.011). LUS can be used to dynamically evaluate the clinical outcome of VAP.