Abstract: OBJECTIVE To study the status of pulmonary infection in patients with general anesthesia undergoing surgery in different posture, so as to provide evidence for the selection of appropriate position in the clinical operation. METHODS A total of 120 cases of general anesthesia patients were chosen from Jun. 2013 to Jun. 2015 in our hospital, according to the operation mode of different patients, who were divided in supine position group and the prone position group, with 60 cases in each group. The samplegs were selected from the gas storage bag mouth, mouth filling and joint connected to the patients in the mouth of anesthesia breathing circuit, before aseptic operation, 4H after aseptic operation and at the end of aseptic operation. The samplegs were under culture and counted. The cultures with colony were separated. After surgery, the patients were followed up for a week, and the patients were observed and recorded. RESULTS From the 360 samples, 78 were detected and the positive rate was 21.66%. The specimens from gas storage bag mouth, mouth filling and the joint connected to the patient in the mouth were detected and positive rate respectively were 1.66%, 45.83% and 17.50%. 4h after anesthesia and at the end of anesthesia, the positive rates of pathogenic bacteria got from gas storage bag mouth, mouth filling and the joint connected to the patient in the mouth were significantly different (P<0.05). The composition ratio of gram negative bacteria was 65.38%, and the composition ratio of gram positive bacteria was 20.52%. Postoperative follow-up showed that 1 case of patients with pulmonary infection in prone position group, pulmonary infection rate was 1.67%; supine position group pulmonary infection patients was in 9 cases, and the infection rate was 15.00%. Compared with the rates of two groups of patients with pulmonary infection, the difference was significant(P<0.05). CONCLUSION During the general anesthesia in operation, prone position compared with supine position is more conducive for the pathogenic microbial colonization on the disposable anesthesia breathing circuit ventilation system, but the supine position may increase the pulmonary infection incidence for the patients with general anesthesia. Therefore, for the prevention of postoperative pulmonary infection in patients with operation, the prone position is better for the patients.