To　study　the　relationship　between　the　diversity　of　the　surface　microbial　community　and　tobacco　flavor,　and　to　improve　tobacco　quality　using　microorganisms.　The　microbial　community　composition　and　diversity　of　14　samples　of　flue-cured　tobacco　from　tobacco-producing　areas　in　Yunnan　with　varying　grades　were　analyzed　by　high-throughput　sequencing.　PICRUSt　was　used　for　predicting　microbial　functions.　A　strain　of　Bacillus　amyloliquefaciens　W6-2　with　the　ability　to　degrade　pectin　was　screened　from　the　surface　of　flued-cured　tobacco　leaves　from　Yunnan　reroasted　tobacco　leave.　The　enzyme　preparation　was　prepared　through　fermentation　and　then　applied　for　treating　flue-cured　tobacco.　The　improvement　effect　was　evaluated　by　measuring　the　content　of　macromolecule　and　the　changes　in　volatile　components,　combined　with　sensory　evaluations.　The　bacterial　communities　on　the　surface　of　flue-cured　tobacco　exhibited　functional　diversity,　consisting　primarily　of　Variovorax,　Pseudomonas,　Sphingomonas,　Burkholderia,　and　Bacillus.　These　bacterial　strains　played　a　role　in　the　aging　process　of　flue-cured　tobacco　leaves　by　participating　in　amino　acid　metabolism　and　carbohydrate　metabolism.　These　metabolic　activity　converted　complex　macromolecules　into　smaller　molecular　compounds,　ultimately　influence　the　smoking　quality　and　burning　characteristics　of　flue-cured　tobacco.　The　pectinase　preparation　produced　through　fermentation　using　W6-2　has　been　found　to　enhance　the　aroma　and　sweetness　of　flue-cured　tobacco,　leading　to　improved　aroma,　reduced　impurities,　and　enhanced　smoothness.　Additionally,　the　levels　of　pectin,　cellulose,　and　hemicellulose　decreased,　while　the　levels　of　water-soluble　sugar　and　reducing　sugar　increased,　and　the　contents　of　esters,　ketones,　and　aldehydes　increased,　and　the　contents　of　benzoic　acid　decreased.　The　study　revealed　the　correlation　between　surface　microorganisms　and　volatile　components　of　Yunnan　tobacco　leaves,　and　the　enzyme　produced　by　the　pectin-degrading　bacteria　W6-2　effectively　improved　the　quality　of　flue-cured　tobacco.　Copyright　©　2024　Weng,　Deng,　Chen,　Yang,　Li,　Zhao,　Ji,　Wu,　Ni,　Zhang,　Wang,　Qi,　Liao,　Chen　and　Zhang.