Polyamide-tethered polyhedral oligosilsesquioxane (POSS) nanocomposites (PAMIP) with well-defined architectures have been synthesized through Michael addition reaction between the maleimide-containing fluorinated new copolyamides (PAMI) with amino-functionalized POSS (POSS-NH2) nanofiller. The chemical structures of the polyamide-POSS nanocomposites were characterized by 1H NMR and Fourier transform infrared spectroscopy. The effects of POSS-NH2 on the morphology and properties of the PAMIP membranes were examined by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction and transmission electron microscopy (TEM) analysis. POSS molecules tethered to polyamide form sphere shaped POSS aggregate cages (phase separated morphology) were confirmed by TEM analysis. All the PAMIP membranes showed very high permeability for different gases compared to PAMI membranes. The increase in permeability is accompanied by increase in diffusivity coefficient of the PAMIP membranes for different gases.