Abstract Development of antifouling membrane to separate oil–water emulsions by low energy consumption approach is an urgent demand. Herein, we report for the first time a grass-like structured composite membrane from array growth of nickel cobalt layered double hydroxide (NiCo-LDH) onto the polydopamine modified polyvinylidene fluoride (PVDF) membrane surface via simple hydrothermal strategy. The surface morphology of as-prepared membrane has controlled by hydrothermal time. The obtained NiCo-LDH/PVDF composite membrane exhibits superhydrophilicity/underwater superoleophobicity for separating both surfactant-free and surfactant-stabilized oil–water emulsions by capillary effect under the driving of gravity. Moreover, with the advantages of antifouling performance, the membrane displays outstanding cyclic performance for long-term application, which is promising for practical oily wastewater treatment.