Abstract: Aroma-producing microorganisms have considerable promise for producing natural flavors and fragrances in an environment-friendly way.In this study,morphological characterization,physiological and biochemical test,and 16S rDNA sequence analysis were performed to identify aroma-producing strain HD-7.Additionally,the aroma compositions from aroma-producing strain HD-7 fermentation were analyzed by gas chromatography-mass spectrometry ( GC-MS)．The result showed that the strain HD-7 was a Bacillus pumilus.A large number of aroma compositions were detected by GC-MS,and the main components included ethyl propionate,acetic acid,n-Propyl acetate,3-hydroxy-2-Butanone with the contents of 25.56%,12.68%,6.80%,4.86%,respectively,among which the ethyl propionate and 3-hydroxy-2-Butanone were widely used as flavors and fragrances．The aroma-producing strain HD-7 is of great application value for production of natural flavors and fragrances．

Key words: aroma-producing bacteria, Bacillus pumilus, gas chromatography-mass spectrometry, aroma compounds, natural flavors and fragrances