Highly meso-porous silicon oxycarbide glasses have been obtained from preceramic hybrid materials aged in NH4OH solutions. Surface characterization reveals the amphoteric character of the surface because of the presence of carbon and silica nanodomains. The dependence of the surface Lewis base constant with the concentration of the NH4OH solution suggests different distribution in the carbon nanodomains because of the addition of the aging solution. Structural characterization reports on the increase in the crosslinking degree in the materials treated in NH4OH, whereas the number of dangling bonds increases significantly in the microporous material taken as a reference.