ObjectiveTo analyze the clinical distribution and antimicrobial resistance change trend of Acinetobacter baumannii（AB） from a geriatric hospital in 2013-2016. MethodsSpecimen source, department distribution, and antimicrobial resistance of AB isolated from all patients in the hospital from 2013 to 2016 were analyzed retrospectively. ResultsFrom 2013 to 2016, 1 712 strains of AB were isolated, AB isolation rates in 2013, 2014, 2015, and 2016 decreased year by year, which were 17.92%, 17.17%, 15.10%, and 11.81%, respectively. AB were mainly isolated from sputum (n=1 524, 89.02%), followed by urine (n=79, 4.61%) and blood (n=37, 2.16%). The main departments of AB isolation were intensive care unit (n=798, 46.61%), department of respiratory medicine (n=507, 29.62%), and neurology department (n=156, 9.11%). Resistance rates of AB to most antimicrobial agents increased in 2013-2016, resistance rates to compound sulfamethoxazole were low (25.68%-65.89%), followed by resistance rates to cefoperazone/sulbactam (54.74%- 68.00%), resistance rates to imipenem were 71.40%-77.42%, to the other antimicrobial agents were all>60%; in 2013-2016, resistance rates of AB to cefepime, cefoperazone /sulbactam, gentamicin, tobramycin, and compound sulfamethoxazole were significantly different (all P<0.05). ConclusionAntimicrobial resistance rates of AB in this hospital is increasing, it is necessary to strengthen the monitoring, promote the rational use of antimicrobial agents, and block the infection and transmission of AB in hospital.