Catastrophic oil spills and their impact on the environment have created a great need to find low-cost, multi-functional materials which are efficient at oil-water separation [1]. In nature, several plants such as lotus leaf which display water-contact angles bigger than 150° are considered to be superhydrophobic [2,3]. In this study, superhydrophobic-superoleophilic nanofibers were prepared via electrospinning of polystyrene (PS) with various percentages of candelilla wax (CW) in dimethylformamide (DMF) and tetrahydrofurane (THF) solvent mixture. Characterization and thermal analysis of the nanofibers have been investigated by the Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC), respectively. The wettability of the nanofiber membranes was determined by water-contact angle measurements. Oil-water separation efficiency was also tested with diesel and vegetable oil. FTIR and DSC results showed that CW was successfully incorporated into PS. It is reported that oil absorption efficiency of PS nanofiber with 2% CW has considerably enhanced. The contact angle of water on PS nanofiber with 2% CW was found to be 153° which is higher than that of neat PS nanofiber (151°) while the contact angle of oil on prepared nanofibers was 0°. PS/CW nanofibers seem to have potential applications in waste-water treatment for oil spill clean up.