ObjectiveTo evaluate clinical efficacy of tigecycline alone or in combination with other antimicrobials in treating infection caused by carbapenemresistant  Acinetobacter baumannii(CRAB). MethodsPatients with hospitalacquired pneumonia (HAP) and/or bloodstream infection in the intensive care unit of a hospital between January 2013 and June 2014 were selected, efficacy of tigecycline treatment was analyzed. ResultsOf 25 patients with CRAB infection, 21 were with HAP, 2 with bloodstream infection, and 2 with both HAP and bloodstream infection.  13 cases were multidrugresistant Acinetobacter baumannii (MDRAB), 10 cases were  extensively drugresistant Acinetobacter baumannii (XDRAB). The susceptibility rate of 25 CRAB isolates to tigecycline was 84%. After treated with tigecycline, white blood cell count(WBC),  Creactive protein (CRP), and procalcitonin (PCT) all significantly decreased (all P<0.01). The clinical effective rate, bacterial clearance rate, and 30day mortality were 68.00% (17/25), 66.67%(14/21), and 28.00% (7/25) respectively; effective rate of 21 cases of HAP was 76.19% (16/21),  1 case of bloodstream infection was effective, 2 cases of HAP combined bloodstream infection died. ConclusionTigecycline is effective in the treatment of HAP caused by CRAB, but the therapeutic effect on bloodstream remains uncertain, further research is needed.