A new system to produce lignin peroxidase (LiP) continuously by Phanerochaete chrysosporium is described. A fixed-bed bioreactor with a pulsing device was used as the optimal bioreactor configuration. Addition of veratryl alcohol (1 mM), tryptophan (1 mM), no Mn2+ addition, low glucose addition rate (60-70 mg l(-1) h) and an atmosphere of O-2 gave maximum LiP activities of 700 U l(-1), which are higher than those previously reported.