Abstract: High performance polyether-ether-ketone (PEEK) thermoplastic composites have the advantages of good impact and fatigue resistance, unlimited ambient temperature storage life, short molding cycles, being recyclable and good reprocessing ability, which have been widely used in aerospace and other industry domains. Powder impregnation method can realize the infiltration of resin particles into fibers by water-based suspension, which has become an effective technical route for preparing continuous fiber reinforced thermoplastic prepregs. This paper focused on the surface characterization of PEEK produced in both domestic and overseas by inverse gas chromatography (IGC) as well as the comparison of microstructure and size distribution. The results show that the dispersion surface energy value of imported PEEK (19.2 mJ/m²) is obviously lower than the domestics (41.1 mJ/m²). The driving force of the adsorption between PEEK particles and polar probe molecules is acid-base interaction in nature, while the surface of PEEK particles is generally alkaline. With higher surface polarity, imported PEEK can more easily disperse into water through the dispersant. By preparing the water-based resin slurry based on the surface characterization results, the thermoplastic prepregs produced with powder impregnation method show excellent quality. The porosity of the powder impregnation prepregs is less than 0.5% and fibers are neatly arranged, with the short beam shear strength of 109 MPa, 30% higher comparing with prepregs produced by traditional hot melt impregnation method.