A dual functional low surface energy coating with polysilazane preceramic precursor is developed to form a silicon-based polymeric film. The result shows that the lowest surface free energy of the fluorinated silicon-based polymeric film is about 28.43 mJ/m2 and its corrosion potential achieves 0.0899 V by the tafel polarization indicating that it has relatively low surface free energy with high corrosion resistance. The water contact angle of the silicon-based polymeric film with polysilazane preceramic precursor diluted in acetone crosslinked at 400 °C can achieve 126.8°. Polysilazane preceramic precursor incorporated with titanium dioxide, TiO2 is able to reduce the surface energy to lower than 30 mJ/m2 for anti-fouling application. Nanoindentation result shows the fluorinated silicon-based polymeric film has the higher elastic recovery rate, 77.3 % representing that fluoride dopant improves its surface toughness. The average hardness and reduced modulus of the silicon-based polymeric film are superior to that of the pure aluminum, showing that this dual functional low surface energy coating provides a relatively high surface strength with high toughness.