The vgb and bleomycin resistance genes could be efficiently transferred into the filamentous fungus Penicillium chrysogenum under help of T-DNA of Agrobacterium tumefaciens LBA4404 and the transferred genes were integrated at a chromosomal locus of P. chrysogenum. Transformation using A. tumefaciens LBA4404 could be enhanced in the presence of acetosyringone (AS) when being carried out in the conidiaand mycelium. The efficiencies of transformation could be improved up to 10 folds compared with conventional techniques for transformation of P. chrysogenum protoplasts.