We have fabricated optical waveguides in Er3+/Yb3+ co-doped silicate glasses by the hydrogen ion implantation, which resulted in a higher refractive index region with a width of around 6.0 mu m to guide near-infrared light as a waveguide core. The thermal stability of the waveguide structure was obtained by the annealing at 200 degrees C for 60 min. The refractive index changes before and after annealing were characterized by the prism coupling method at 1.539 mu m. The measured refractive index corresponded well with that of the calculated mode by a numerical analysis based on the RCM. The cross-sectional image of the proton-implanted waveguide was recorded by an optical microscope. The propagation properties of 1.539-mu m light in the waveguiding layer of the structure was calculated by the FD-BPM. Considering the importance of waveguide structure in the Er3+/Yb3+ co-doped silicate glass for integrated photonic components, the thermal-stable proton-implanted waveguide can be a starting point for the development of on-chip devices in the near-infrared region.