In this research work, sol–gel-derived oxygen barrier coatings on elastic substrate were reported. The synthesis process, layers deposition, and characteristic of physical and functional properties of films were presented. Two silica-based hybrid systems were studied where silicon precursors with different carbon chain length (C3 and C8) were used during the sol–gel synthesis. The microscope images showed that the produced coatings were free of defects and had smooth surface with more hydrophobic character than polyethylene terephthalate used as a substrate. The coatings were designed to improve barrier parameters for oxygen transmission through the foil, that was achieved by one-side layer deposition using spin-coating technic. The oxygen transmission rate of the substrate covered with one of the two different coatings examined by manometric method decreased by 35% or 54% of the initial value. Lower oxygen permeability was achieved for the sample containing octyl groups, which showed higher content of carbon atoms on the surface, higher value of water contact angle, and lower roughness parameters.