A hydrophobic-oleophilic nanofibrous membrane was successfully produced by incorporating cellulose nanocrystals (CNC) into polyvinylidene fluoride (PVDF) via an electrospinning process. The effects of levels of CNC loading on membrane microstructure, mechanical properties, water and oil contact angle and efficacy of separating oil from water-in-oil emulsions were investigated. The results demonstrated that the incorporation of CNC improved the flux of emulsion separation of the fabricated fibrous membranes by optimizing microstructure and porosity. For water-in-toluene emulsions, a higher flux of 5842 L m(-2) h(-1) with high separation efficiency of 97% was obtained for membranes with CNC addition of 4 wt%, 4 times greater than that of pure PVDF membrane (1495 L m(-2) h(-1)). Most importantly, as increasing CNC loading levels, membranes demonstrated good mechanical performance while being easily recycled, which is environmentally friendly, flexible and sustainable.