Natural aromatic compounds are in growing demand in the food and pharmaceutical market. Due to limited sources for natural aroma compounds, there is an increasing interest in developing different sources for vanillin and another aromatic aldehydes. Some microbial species have been reported to produce aromatic aldehyde as an intermediate product in the degradation pathway of phenylpropanoids. The present work was carried out to isolate microbial species, capable of transforming isoeugenol to vanillin and its metabolites. Bacillus firmus strain JAA1 isolated from soil sample was found to transform isoeugenol into vanillin. The ability to produce vanillin from isoeugenol as substrate was screened through resting cells. The bacterial strain possessed the tolerance to grow in presence of isoeugenol as the sole carbon source. The bioconversion of isoeugenol to vanillin by the strain Bacillus firmus JAA1 was detected in the growing culture and its metabolite was detected through gas chromatography mass spectroscopy.