Polyglycerol-10(PG) was used as stabilizer to simultaneously ex-foliate and functionalize hexagonal boron nitride (h-BN) under ultrasonic condition. The h-BN nanowires functionalized by PG (GB) were characterized by FT-IR, TG, AFM and TEM. The prepared GB was used as the anticorrosive filler of waterborne polyurethane (WPU) coating, and the composite coatings with different amount of GB(0，0.5%，1.0%，2.0%) were prepared. The water contact Angle, water absorption, adhesion loss, thermal and mechanical properties of different coatings were investigated. Finally, the corrosion behaviors of WPU and PU/GB composite coatings in 3.5%NaCl aqueous solution were evaluated by electrochemical workstation. The results show that GB nanoparticles can significantly enhance the water resistance, thermal stability, mechanical properties and corrosion resistance of WPU coatings.