The invention discloses a fiberglass enhanced polyphenyl thioether/polyphenylether composite material and a preparation method thereof. The composite material is mainly prepared by the following raw materials: polyphenyl thioether, polyphenylether, fiberglass, mineral filler, a compatibility agent, an antioxidant and a processing aid. The preparation method of the fiberglass enhanced polyphenyl thioether/polyphenylether composite material comprises the following steps of: (a) firstly, respectively blasting and drying polyphenyl thioether resin and polyphenylether resin; (b) weighting the polyphenyl thioether resin and the polyphenylether resin which are dried, the mineral filler, the compatibility agent, the antioxidant and the processing aid; (c) mixing the dry materials in the step (b) to obtain a compound; and (d) adding the compound in the step (c) and the fiberglass to a double screw extruder for melt blending and pelleting. The fiberglass enhanced polyphenyl thioether/polyphenylether composite material can unconspicuously lower the temperature-resistant level and the rigidity of the polyphenyl thioether resin, further improve the molding accuracy of the polyphenyl thioether resin and decrease the cost.