ObjectiveTo evaluate antimicrobial resistance and resistance mechanisms of mucoid Pseudomonas aeruginosa (P. aeruginosa), and provide reference for the clinical use of antimicrobial agents.MethodsAll P. aeruginosa strains isolated from patients were identified by API strip, antimicrobial susceptibility testing was performed by KirbyBauer disk diffusion method, data were analyzed by WHONET5.4 software.ResultsOf 12 kinds of antimicrobial agents, resistance of nonmucoid P. aeruginosa to gentamicin, cefotaxime, aztreonam, cefepime, ciprofloxacin and levofloxacin were significantly higher than mucoid P. aeruginosa (P<0.05), but the resistance to imipenem, meropenem, piperacillin/sulbactam, amikacin, ceftazidime and cefoperazone were not significantly different（P>0.05）. Before and after the combination antimicrobial therapy for mucoid P. aeruginosa infection, resistance of mucoid P. aeruginosa to 12 kinds of antimicrobial agents were as follows : resistance to imipenem and meropenem was the same; to amikacin and cefotaxime after therapy was higher than before therapy （P<0.05）; resistance to the other antimicrobial agents showed different degrees of change.Conclusion In vitro antimicrobial resistance of mucoid P. aeruginosa is low, but in vivo effectiveness of antimicrobial agents is not ideal, therapeutic effect can be achieved by combination use of in vitro susceptible antimicrobial agents and drugs which can inhibit bacterial biofilm.