Interfacial micromechanical performance of carbon fiber (CF)-reinforced polyphenylene sulfide (PPS) composites was studied by the microbond test, which has been well accepted as the most important micromechanical test for evaluating the interfacial properties between the fiber and matrix. The effect of annealing treatment and atmospheric plasma treatment on the interfacial adhesion and micromechanics of PPS/CF composites was investigated. The results showed that the apparent interfacial shear strength ((app)) value of microcomposites increased from 33.5 +/- 4.3 to 43.9 +/- 2.3MPa after annealing. Moreover, plasma-modified CF was characterized by scanning electron microscope and X-ray photoelectron spectroscopy. It was shown that the surface roughness was improved; the O/C atomic ratio was increased from 16.2 to 28.5%. Though hydrogen and covalent bondings were induced at fiber/matrix interface, the (app) values of PPS/CF composites decreased to 36.4 +/- 1.0MPa with atmospheric plasma treatment, due to the remove of the size layer coated on the surface of CF.