Fiber-reinforced polymer composites, which effectively replace traditional materials in various applications, are still the subject of intensive research and improvement of manufacturing technologies. This paper brings the study of plasma-enhanced fiber-matrix interfacial bonding improving the properties of aramid, glass, and flax reinforcing fabrics, the most frequently used in laminated FRP composites. Plasma treatment was realized by Diffuse Coplanar Surface Barrier Discharge (DCSBD). The physicochemical surface properties, such as wettability, morphology, and chemical changes of the plasma-treated fabrics, were determined by the water contact angle, Washburn method, and X-ray photoelectron microscopy. The fiber-matrix adhesion was investigated by the peel-off test measurement. Plasma treatment of aramid, glass, and flax fabrics increased their wettability, enhanced the surface chemical activity, as well as significantly strengthened their interfacial bonding strength at the fiber-matrix interface.