With the rapid industrial development, the discharge of oily wastewater has increased and polluted the environment. The conventional oil/water separation method has problems, such as generating harmful by-products, high operating costs, and low efficiency. For this reason, research on the development of ideal oil/water separation materials is being actively conducted. In this work, a hydrophobic mesh filter with excellent separation efficiency and separation speed was prepared through the surface coating of stainless steel Mesh (SUS Mesh), which has a large aperture size. After carbon coating on the surface of the SUS Mesh using the physical vapor deposition method, hydrophobicity was improved by giving fluorine functional groups to the surface using fluorine plasma. The manufactured mesh filter separated the oil at a high flux (6,062 Lm2h-1) in a horizontal condition without external force, and at a high speed of fewer than two minutes, with a separation efficiency is 99.88%. Very high separation efficiency was observed. In addition, the average efficiency of 99.77% was maintained even in continuous oil/water separation. The hydrophobic mesh filter fabricated by a simple process in this study can be evaluated as a promising oil/water separation material that can be actually applied to separate oil from oily wastewater.