Plasma treatment, an environmentally safe method, was applied for surface modification of carbon fibers (CFs) and polyphenylene sulfide (PPS) fibers. The morphology, crystallization property, thermal stability, and chemical properties of CF/PPS composites were determined, respectively, by scanning electron microscopy, differential scanning calorimetry, thermogravimetry analysis, and X-ray photoelectron spectroscopy. Interfacial micromechanical performance of CF/PPS composites was investigated by microbond test. The influence of plasma treatment on the apparent interfacial shear strength ( τapp) of CF/PPS micro-composite was systematically evaluated. The plasma treatment of CF reduced the τapp of the micro-composite by 13.7% and that of CFs and PPS fibers by 3.4%. However, the plasma-treated PPS fibers increased the τapp of the micro-composite by 17.1%. The present study demonstrates that matching of polarity between CF and the resin plays a great role in reinforcement of interfacial property.