Abstract: A novel method for preparing thermosetting modified polyphenylene ether was investigated by introducing allyl group into polyphenylene ether (PPE). It was prepared by the reaction of brominated PPE and a Grignand reagent. The allylated PPE was analyzed by ()~1H-NMR and FTIR. The curing process was also studied breifly. The properties of cured allylated PPE were measrued and the results showed that the cured allylated PPE had desired dielectric properties such as a low dielectric constant and dielectric dissipation factor, excellent solvent resistance and low moisture absorption.