ObjectiveTo evaluate the causes and control measures of outbreak of Acinetobacter baumannii (A. baumannii) pulmonary infection in an intensive care unit (ICU), so as to reduce the incidence of such infection.MethodsEpidemiological investigation and environmental hygiene monitor were performed on 7 cases of clustering A.baumannii pulmonary infections in ICU within 2 weeks by prospective and retrospective investigation, various risk factors were analyzed and appropriate measures were taken to control the infection.ResultsPrevalence of pandrugresistant A. baumannii infection in ICU was 28.00%(7/25); ICU environment was contaminated, drugresistant pattern of A. baumannii from sputum culture and environment was similar, A. baumannii infection was controlled after appropriate measures were taken.ConclusionEnvironmental contamination in ICU was the cause of the outbreak of A. baumannii pulmonary infection. Environmental cleaning can prevent and control outbreak of A. baumannii infection.