Two DNA-mediated transformation systems were successfully adapted to Aspergillus ficuum. Both the Escherichia coli hygromycin B resistance gene and the A. nidulans amdS gene transformation systems produced stable A. ficuum NRRL 3135 transformants. Cotransformation with the E. coli lacZ gene was also achieved with the hygromycin B system. In cotransformation a second unselected gene, in this case the lacZ gene which codes for β-galactosidase, was also integrated and expressed in hygromycin B transformants. Since both of these transformation systems utilized dominant selection markers, they are potentially useful in other genetically uncharacterized filamentous fungi.