In this research, a novel superhydrophilic/ superoleophobic thermoplastic polyurethane@graphitic-carbon nitride@perflourooctanoic acid (TPU@g-C3N4 @PFOA) coated stainless steel mesh was prepared to separate water/oil emulsion. g-C3N4 nanosheets were synthesized with a facile thermal condensation process followed by exfoliation using acid. TPU as a binder is commercially available and provides strong bonding of the nanocomposite coating to the substrate. Wettability characteristics of nanocomposite coated mesh showed the water contact angle of 18.9° and oil contact angle of 151°, which confirmed the special wettability of superhydrophilicity and superoleophobicity. The prepared nanocomposite-coated filter with the surface energy of 92.87 mN/m (dispersive and polar surface energy of 0.199 and 92.68 mN/m) was able to separate water from a 10 wt % water/oil emulsion. Ultimately excellent water–oil separation efficiency of 99% and the filtration flux of 50.5 L.m−2.h−1 were attained under gravity. The particular behavior of the surface is justified with small pore size of mesh, higher roughness and superoleophobic wettability due to the presence of g-C3N4 nanosheets, as well as with the reduction of the surface energy of the synthesized TPU@g-C3N4 by PFOA, as a surfactant with the fluorine tail groups. As-prepared mesh can also separate free crude oil–water mixtures with the separation efficiency and flux of 99.9% and 2157.4 L.M−2.h−1, respectively.The anti-fouling and mechanical stabilities of the as-prepared coated mesh were investigated. This result implied that the as-prepared water-removing filter has great potential for separation of the water-in-oil emulsion, which has long been a problem in industry and is often separated using oil-removing filters in the literature.