Objective To investigate the changes of antimicrobial resistance of bacteria from bronchoalveolar lavage fluid (BALF) specimens in China. Methods Data of BALF specimens were extracted from China Antimicrobial Resistance Surveillance System (CARSS) surveillance report in 2014-2019, antimicrobial resistance was analyzed by WHONET 5.6 software. Results From 2014 to 2019, a total of 140 321 strains of bacteria were isolated from BALF specimens, the top 5 bacteria were Pseudomonas aeruginosa (19.1%), Acinetobacter baumannii (16.6%), Klebsiella pneumoniae (16.6%), Staphylococcus aureus (7.8%) and Streptococcus pneumoniae (6.2%). Antimicrobial susceptibility data of 6 years showed that isolation rates of methicillin-resistant Staphylococcus aureus (MRSA) were 52.3%, 55.5%, 51.4%, 42.8%, 40.6% and 37.9% respectively, vancomycin-, teicoplanin- and line-zolid-resistant Staphylococcus aureus were not found. The overall resistance rates of Streptococcus pneumoniae to penicillin were 1.0%-4.4%, penicillin-nonsusceptible Streptococcus pneumonia (PNSP) showed a downward trend year by year; except for compound sulfamethoxazole, resistance of Klebsiella pneumoniae to other antimicrobial agents increased year by year, especially for carbapenems, resistance was significantly higher than that of Esche-richia coli and Enterobacter cloacae. Among non-fermentative bacteria, resistance rates of Pseudomonas aeruginosa were relatively low, most were below 30%; resistance rates of Acinetobacter baumannii to all tested antimicrobial agents didn’t change much generally, but its resistance rates to most antimicrobial agents were relatively high, most were more than 50%. Conclusion Gram-negative bacilli are the main pathogens isolated from BALF specimens in China, and antimicrobial resistance is serious. It is suggested that high-quality BALF specimens should be sent for clinical examination, pathogen detection should be paid attention to, and antimicrobial agents should be used rationa-lly according to the corresponding antimicrobial resistance surveillance data.