Granular activated carbon (GAC) was incorporated into hollow fiber membrane bioreactors for the biodegradation of 1,000 mg phenol l(-1) stop through immobilization of Pseudomonas putida. The phenol was removed within 25 h in the hybrid bioreactor, comparing with 31 h for a GAC-free bioreactor. Sorption, biodegradation, desorption, and bioregeneration were four steps for the phenol removal during batch operation.