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<i>Aspergillus fumigatus</i> LMB-35Aa, a saprophytic fungus, was used for cellulase production through biofilms cultures. Since biofilms usually favor virulence in clinical strains, the expression of the related genes of the LMB 35-Aa strain was analyzed by qPCR from the biomass of planktonic cultures and biofilms developed on polyester cloth and polystyrene microplates. For this, virulence-related genes reported for the clinical strain Af293 were searched in <i>A. fumigatus</i> LMB 35-Aa genome, and 15 genes were identified including those for the synthesis of cell wall components, hydrophobins, invasins, efflux transporters, mycotoxins and regulators. When compared with planktonic cultures at 37 °C, invasin gene <i>calA</i> was upregulated in both types of biofilm and efflux transporter genes <i>mdr4</i> and <i>atrF</i> were predominantly upregulated in biofilms on polystyrene, while <i>aspHs</i> and <i>ftmA</i> were upregulated only in biofilms formed on polyester. Regarding the transcription regulators, <i>laeA</i> was downregulated in biofilms, and <i>medA</i> did not show a significant change. The effect of temperature was also evaluated by comparing the biofilms grown on polyester at 37 vs. 28 °C. Non-significant changes at the expression level were found for most genes evaluated, except for <i>atrF</i>, <i>gliZ</i> and <i>medA,</i> which were significantly downregulated at 37 °C. According to these results, virulence appears to depend on the interaction of several factors in addition to biofilms and growth temperature.