ObjectiveTo assess the methodological quality of guidelines for bronchoscopic alveolar lavage. MethodsCNKI, VIP, WanFang Data, CBM, Web of Science, PubMed, EMbase databases and medlive.cn, the National Guideline Clearinghouse (NGC), the National Guideline International Network (GIN), the Scottish Intercollegiate Guidelines Network (SIGN), the National Institute for Clinical Excellence (NICE), and the World Health Organization (WHO) websites were electronically searched to collect guidelines of bronchoscopic alveolar lavage from inception to December 2020. Two reviewers independently screened literature, extracted data, and assessed the methodological quality of the guidelines by using AGREE Ⅱ tool. ResultsA total of 19 guidelines were included, with 5 from China, 5 from the USA, 3 from Europe, 2 from the UK, 1 from Australia, 1 from Israel, 1 from Spain, and 1 from India. The average standard score rates of the 19 guidelines in the six fields were 50.73% for scope and purpose, 20.02% for participants, 15.13% for formulation rigor, 36.40% for clarity of presentation, 3.51% for applicability, and 22.37% for editorial independence.ConclusionsThe quality of bronchoalveolar lavage guidelines remains relatively low.