Acremonium chrysogenum is the natural producer of the beta-lactam antibiotic cephalosporin C and therefore of significant biotechnological importance. Here we identified and characterized the xylanase-encoding xyl1 gene and demonstrate that its promoter, xyl1 P , is suitable for conditional expression of heterologous genes in A. chrysogenum. This was shown by xylose and xylan-inducible xyl1 P -driven expression of genes encoding green fluorescence protein and phleomycin resistance. Moreover, we demonstrate the potential of the xyl1 P promoter for selection marker recycling. Taken together, these finding will help to overcome the limitation in genetic tools in this important filamentous fungus.