ObjectiveTo realize the distribution and change in antimicrobial resistance of common pathogens causing acute lower respiratory tract infection (LRTI) in children, and provide evidence for rational use of antimicrobial agents.MethodsData about pathogens from children with LRTI in a hospital between January 2011 and December 2013 were analyzed statistically. ResultsOf 934 isoalted pathogenic strains, 728 (77.94%) were gram  negative bacteria, the major were Klebsiella pneumoniae (n=278), Escherichia coli (n=216), Enterobacter cloacae(n=85), and Pseudomonas aeruginosa(n=63). The isolation rate of gram  positive bacteria was 20.87%(n=195),  the major were Staphylococcus  aureus(n=132) and Streptococcus pneumoniae(n=49). Antimicrobial susceptibility testing results revealed that sensitive rate of gramnegative bacteria to imipenem, meropenem,and amikacin were all 100.00%, to ceftazidime/clavulanic acid and piperacillin/tazobactam were relatively low, to cephalosporins increased year by year. Sensitive rates of the main gram  positive bacteria to vancomycin were both  100.00%, to erythromycin  and clindamycin were relatively low. ConclusionThe major pathogenic bacteria causing LRTI in pediatric department are gram  negative bacteria, antimicrobial resistance rates increased year by year, management of antimicrobial use in children should be strengthened to prevent the occurrence of multidrugresistant organism infection.