Provided are a polyphenyl ether resin composition and a prepreg and a laminated board containing same. The polyphenyl ether resin composition comprises the following components: (1) a tetrafunctional or higher multifunctional acrylate-modified thermosetting polyphenyl ether resin; and (2) a vinyl resin cross-linking agent, the weight of the vinyl resin cross-linking agent being 40-100 parts by weight based on 100 parts by weight of the tetrafunctional or higher multifunctional acrylate-modified thermosetting polyphenyl ether resin. The modified thermosetting polyphenyl ether resin, due to containing a tetrafunctional or higher multifunctional acrylate active group, can cross-link more vinyl resin cross-linking agents. Not only the prepared high-speed electronic circuit substrate has low dielectric constant and dielectric loss, but also double bonds in side chains of the vinyl resin cross-linking agent are reacted completely in a resin curing system, so that the high-speed electronic circuit substrate has a better thermo-oxidative aging resistance.