In this study, water vapor barrier film was prepared by stacking organic layer and inorganic layer respectively on PET substrate. Perhydropolysilazane(PHPS) was the precursor which goes moisture-curing reaction at low temperature to form silica oxide (SiOx), the inorganic layer. Polyurethane acrylate and epoxy acrylate were UV oligomers which combine with cross-linking monomer to formulate UV-curing resin, the organic layer. This study focus on the composition of organic layer affects the adhesion property, flexibility, thermal resistance and durability of water vapor barrier film. From the experiment results, the UV-curing organic layer formulated by polyurethane acrylate oligomer, epoxy acrylate oligomer, and pentaerythritol triacrylate (PETA) monomer performs excellent flexibility, thermal resistance and durability. And the organic layer shows very good adhesion property between PET substrate and silica oxide inorganic layer because of containing hydroxyl group. The transmittance of visible light of this organic and inorganic stacked monolayer barrier film is more than 90%. The surface roughness Ra is 0.38 nm and Rq is 0.57 nm. WVTR of this monolayer barrier film is below than 0.55 g/m2•day. Even after 1000 times bending test, WVTR is still below than 0.6 g/ m2•day. It is believed that by preparing organic and inorganic layers respectively and forming a multilayer barrier film could meet flexible electronics barrier property requirement. And this multilayer barrier film will be applied to flexible electronics encapsulation in the near future.