A process for preparing PPE microspore dispersion includes steps of: dissolving a high-molecular polyphenylene ether in a first solvent at 45-110° C. to form a dissolution liquid; adding processing aids and well mixing the dissolution liquid into a dispersed phase; cooling the dissolution liquid to 42-80° C., and adding a second solvent to generate PPE microspores via PPE to wrap around the processing aids; cooling the dissolution liquid to 0-40° C. to obtain PPE microspore dispersions for use in application for impregnation processes performed below 40° C., thereby high-temperature impregnation equipment are no longer needed, and copper clad laminates made of using the PPE microspore dispersion enjoy excellent physical properties including high Tg, low Dk, low Df and high copper foil's peel strength.