the present invention provides a process for regenerating a catalyst for producing e - caprolactam comprising the steps of adsorbing a silicon compound on a zeolite catalyst that had been used for a beckmann rearrangement reaction of cyclohexanone oxime and contacting the catalyst with an aqueous solution containing a compound selected from a quaternary ammonium compound , lower alkylamines and ammonia . the present invention also provides a process for producing e - caprolactam comprising subjecting cyclohexanone oxime to the beckmann rearrangement reaction in the presence of the catalyst thus regenerated .