The deactivation and regeneration of B2O3/TiO2-ZrO2 catalyst for the vapor phase Beckmann rearrangement of cyclohexanone oxime to epsilon-caprolactam were studied. The fresh, deactivated and regenerated catalysts were characterized by using adsorption of nitrogen, X-ray diffraction (XRD). thermogravimetry (TG) and NH3-temperature-programmed desorption (NH3-TPD) techniques, The crystal structure and pore size distribution of the catalyst were retained after reaction, but the number of acid sites decreased significantly, There was a relationship between the amount of coke deposited on the catalyst and the decline in catalytic activity. These results suggest that the coke deposition on the surface of catalyst is mainly responsible for the catalyst deactivation. The catalytic activity can be recovered completely after calcining the deactivated catalyst in air flow at 600 degrees C for 8 h. (c) 2005 Elsevier B.V. All fights reserved.