A novel unparalleled anti-permeable superhydrophobic coating was obtained by supplementing PLA/CH2Cl2 solution with silane coupling agent and hydrophobic silane nanoparticles that prepared by sol-gel reaction between hexadecyltrimethoxysilane and tetraethyl orthosilicate. The structure and morphology of the coating was characterized by FTIR and SEM. FTIR indicated silane coupling agent has not participated chemical reaction. SEM revealed that the superhydrophobic originated from the hierarchical structure morphology. The water contact angle measurement indicated the hydrophobic silane nanoparticles considerably improved the water-repellency and achieved superhydrophobicity：above 150o This superhydrophobic coating possessed the advantage of simple preparation, excellent resistance of water penetration as well as environmentally friendly. In the time-span range of 10min-20min, compared with the coating of hydrophobic silane nanoparticles (contact angle decreasing speed 150o/min) and pure coating of PLA/CH2Cl2 solution, (contact angle decreasing speed 9.5o/min) the hydrophobic silane nanoparticles/PLA solution coating has improved resistance of water penetration to a great extent, contact angle decreasing speed was merely 8o/min. The excellent anti-permeability towards water was achieved by incorporating the hierarchical structure of hydrophobic silane nanoparticles with the good film-forming property of PLA.