A commercial laccase was immobilized on the surface of PAN/MMT electrospun composite nanofibrous membrane,which was used in the homemade membrane reactor for phenol treatment.The activity of the laccase immobilized on PAN/MMT composite nanofibers was as high as 6.25 U/mg nanofibrous membranes,and the existence of laccase on nanofibers surface was confirmed by SEM images,via which a novel strip-like structure twined around the fiber was observed.During the reaction,two phenolic compounds (catechol and guaiacol) were effectively polymerized by the enzyme catalysis,and the reaction products were adsorbed by the PAN/MMT composite membrane.