The development of biocatalytic methods has allowed the preparation of a wide variety of products with high added value through simple, selective, economical and environmentally friendly processes. In this work, the microbial transformation of arylpropanoide substrate trans-cinnamaldehyde using the fungus Aspergillus sp. was investigated. The process is carried out in liquid media culture Sabouraud y CzapeckDox to an average temperature 24 o C, relative humidity between 45 and 60%, and with agitation at 120 rpm on a orbital shaker. The biotransformation of the substrate generated mainly the metabolic products 3-phenyl-1-propanol, cinnamyl alcohol, 3-phenylpropanal, 3-phenylpropyl acetate, cinnamyl acetate,