By analyzing multiple regression, cigarette smoking (OR=2.6; 95% CI: 1.32 - 5.1; p=0.006), coma (OR=2.76; 95% CI: 1.27 - 6; p=0.011), low blood albumin (OR=2.57; 95% CI: 2.37 - 12.3; p=0.008), blood transfusion (OR=3.17; 95% CI: 1.27 - 7.9; p=0.014), using PPIs (OR=1.66; 95% CI: 1.11 - 2.48; p=0.014), tracheotomy (OR=17.8; 95% CI: 3.36 - 94.2; p=0.001) were independent risk factors for HAP at ICU significantly (p<0.05).