Abstract: In this paper, SiO₂ with different particle sizes was modified by hydrothermal method, and low surface energy superhydrophobic materials were obtained. The effect of particle size on superhydrophobic properties was studied, and the surface morphology and wettability of the material were analyzed by fourier transform infrared spectrometer, field emission scanning electron microscope, X-ray diffraction, and contact angle measuring instrument. The results show that the modified SiO₂ has enhanced hydrophobicity. And the smaller the particle size, the rougher the surface of the material and the stronger the hydrophobicity. Nanometer SiO₂ is much more hydrophobic than micrometer SiO₂, and its static contact angle can reach 158.0° ± 5.4°, and the rolling angle is less than 2°. Superhydrophobic materials have broad application prospects.