Abstract: In order to prepare stainless steel filter with controllable wettability and oil-water separation property, a layer of zinc oxide was grown on the surface of stainless steel by hydrothermal method to construct micro-nano roughness. Then, a stainless steel filter with controllable wettability was successfully prepared by modification of fatty acids with different chain lengths. The wettability, surface morphology and composition of the samples were analyzed by contact angle measuring instrument, FTIR, SEM and XRD, respectively. The oil-water separation efficiency and reusability of the samples were characterized by oil-water separation device. The results show that the wettability of the samples modified by fatty acids with different chain lengths varie from superhydrophilic to superhydrophobic, ranging from 0° to 158°, and the oil remain at 0°. The oil-water separation efficiency is 92%-98%, and it still has oil-water separation performance after repeated use for 50 times. Therefore, the prepared stainless steel filter has excellent oil-water separation performance and good reuse performance.