Agrobacterium tumefaciens mediated transformation has been widely used in plant genetic engineering, and in some of the Filamentus fungi including Penicillium chrysogenum and Aspergillus nidulans as well. We have developed an adapted A. tumefaciens mediated transformation protocol for A. chrysogenum, which has a higher transformation efficiency than the PEG mediated method , and more importantly, this protocol can also be applied in A. chrysogenum high-yield strain. This is the first report of A. tumefaciens mediated A. chrysogenum transformation.