Aluminosilicate gels of different alumina and silica ratios and cordierite MgAkSi5O1 gels were made by the nanocomposite sol-gel route and sintered to obtain highly dense materials. Measurements of the dielectric constant K and dissipation (loss) as a function of temperature and frequency showed that low dielectric constants of 5. 6 and 5. 4 at 1 and 4 MHz respectively for cordierite and of 6. 9 and 6. 7 at 1 and 4 MHz respectively for mullite at 25C were achieved. Aluminosilicate materials prepared with 10 wt A12O and 90 wt SiO showed the lowest dielectric constants of 4. 27 and 4. 20 at 1 and 4 MHz respectively.