A novel nanofibrous membrane for oil/water separation is reported. Electrospinning was employed to fabricate the nanofibrous membrane from a porous polymer of fluorine-containing triptycene-based polyimide (FTPI), which was synthesized and characterized by NMR, FT-IR and TGA. With porous properties and highly hydrophobic features, the membrane of FTPI showed a large water contact angle (WCA) (121°), high flux and great separation efficiency for oil/water mixtures. We believe that the fluorine-contained nanofibrous membranes may be considered as promising candidates for oil/water separation.