Porous glasses having nano-pores were prepared using a sol-gel method, where the proton conduction was investigated to relate with the pore structure. The prepared porous glasses absorb the water in an ambient atmosphere and consequently increase the electrical conductivity. The conductivity was proportional to the logarithm of the number of water molecules. The effect of the pore-size on the proton conduction was also investigated. In glasses having pores with size smaller than similar to5 mn, the water molecules totally fill the pores, in which the motion of the water molecules is restricted in the pore and the adsorbed waters are well retained even under low humidity. The conductivity of this glass was high in temperature range down to -20degreesC. The conductivity at 150degreesC was similar to170 mS/cm. We could conclude that the sol-gel-derived glasses have potential for the electrolyte of the fuel cell operating at temperature from -20 to 150degreesC.