Nano-porous ceramic membranes was synthesized by the sol-gel method. Gas permeation of hydrogen and nitrogen was determined by single composition gas. Pore size $0.1{mu}m$ and porosity 32% of flat type ${alpha}-Al_2O_3$ substrate was manufactured. An intermediate ${gamma}-Al_2O_3$ layer with pore size of 4 nm was formed by dip-coating. Polymeric silica sol was synthesized by acid catalyzed hydrolysis and condensation of tetra-ethyl-ortho-silicate. Supported membranes on alumina were prepared by dipping and calcining. He, $N_2$ permeation experiments with nanoporous sol-gel modified supported ceramic membranes were peformed to determine the gas transport characteristics. $He/N_2$ permselectivity around $100{sim}160$ and helium permeation in the order of $10^{-7}mol/m^2{cdot}s{cdot}Pa$ were measured in the temperature range of $303{sim}363K$.