Zeolites were synthesized from fly ash by the NaOH fusion method employing three different NaOH/fly ash weight ratios and the potential of these fly ash-derived zeolites as pyrolysis catalysts was assessed in terms of the yield and simulated boiling point distribution of the liquid pyrolysis products. The physical properties of the fly ash-derived zeolites were characterized and related to their catalytic performance for pyrolysis of polypropylene. It was found that H(+)-exchanged fly ash-derived zeolites were as effective as commercial HY zeolite. The catalytic performance of H(+)-exchanged fly ash-derived zeolites was the most satisfactory with the NaOH/fly ash weight ratio of 1.2. For the mass percentage of 80% on the simulated boiling point distribution curve, the boiling temperature obtained using this zeolite was significantly lower than that obtained without zeolite by as much as 108 ℃. This phenomenon was related to the formation of zeolite materials such as faujasite.