Abstract: Objective:To investigate the distribution and antibiotic resistance of pathogens isolated from nosocomial lower respiratory tract infection for rational antimicrobial therapy.Methods:Kirby-Bauer method was used to test the drug susceptibility of clinical isolated pathogenic bacteria from 3 024 patients sputum.The data were analyzed by WHO NET 5.4 software.Results:In 3 024 clinical isolated pathogenic bacteria,the top five pathogens were P.aeruginosa,K.pneumoniae,A.baumanii,S.aureus and E.coli.The overall drug resistance rate of P.aeruginosa was low,A.baumanii was multi-drug resistant pathogen,the resistance rate of enterobacteriace to antibiotics was increased in recent years except imipenem and meropenem,the rate of methicillin resistant S.aureus was high in S.aureus,and was shown multiple resistance to antibiotics.Conclusions:Gram-negative bacilli are the major pathogens in nosocomial lower respiratory tract infection,antibiotic resistance becomes more prevalent in some major pathogens.