The purpose of the present Letter is the use of dielectric relaxation for investigating percolation phenomena in sol-gel glasses with different catalysts. The broadband dielectric spectroscopy method was employed to investigate glasses of fine porosity produced via the sol-gel route with different catalysts. The study was carried out in the frequency range of 20 Hz to 1 MHz and temperature interval - 100 degrees C to + 150 degrees C. The dielectric response data were analyzed both in frequency and time domains and then interpreted in terms of the various non-Debye relaxation processes. The mechanisms of the processes are discussed. One of them is associated with percolation of electric excitation along the developed fractal structure of connected pores.