ObjectiveTo understand clinical distribution and antimicrobial resistance characteristics of Pseudomonas aeruginosa(P. aeruginosa) isolated from hospitalized patients, so as to provide reference for the empiric use of antimicrobial agents and control of healthcareassociated infection(HAI). MethodsClinical distribution and antimicrobial susceptibility testing results of P. aeruginosa isolated from patients in a hospital between 2012 and 2016 were analyzed retrospectively, statistical analysis were conducted based on different wards, specimen types and age groups. ResultsA total of 2 432 strains of P. aeruginosa were isolated from 2012 to 2016, most of which were isolated from intensive care unit(ICU) (n=727, 29.89%), the main specimen was sputum(n=2 064，84.87%）. Resistance rates of P. aeruginosa to other antimicrobial agents except piperacillin/tazobactam in each year from 2012 to 2016 were significantly different(all P<0.05). Resistance to piperacillin, ceftazidime, cefepime, imipenem, meropenem, levofloxacin, and ciprofloxacin decreased after peaked in 2014; resistance rates to amikacin, gentamicin, and tobramycin were all low, showing decreased trend year by year(all P<0.05). Except resistance rates to cefepime and tobramycin, resistance rates of P. aeruginosa from sputum specimen were all higher than other specimens(all P<0.05). Resistance rates of P. aeruginosa isolated from patients aged≥65 years to most antimicrobial agents were significantly higher than those isolated from patients aged＜65 years(all P<0.05). Except resistance rates to gentamicin and tobramycin, resistance rates of P. aeruginosa isolated from ICU were higher than those isolated from other departments, which were 7.71%-66.02%. Resistance rate of P. aeruginosa isolated from department of surgery were relatively low, which were 1.69%-11.86%. ConclusionClinical distribution of antimicrobial resistance of P. aeruginosa is obviously heterogeneity, empiric antimicrobial use and formulation of HAI monitoring measures should be based on the data of antimicrobial resistance in different wards, different infection sites, and different age.