One new polymerizable fluorescent disperse dye (PEANI) based on 1,8-naphthalimide was synthesized via reaction of 2-(2-hydroxyethyl)-6-(1-pyrrolidinyl)-1H-benzo [de]isoquinoline-1,3(2H)-dione (PAENI) with acryloyl chloride firstly. Dye's structure and fluorescent properties were carefully investigated using nuclear magnetic resonance (H-1-NMR), UV-Vis and fluorescent spectra. Then the yellow copolymer (F-PAN) of PEANI and acrylonitrile was obtained through radical polymerization. Fluorescent nanofiber membrane could be prepared by electrospinning of the F-PAN solution in N,N-dimethylformamide solvent and strong green fluorescent emission located around 510 nm could be found (lambda(ex)=450 nm). The electrospun F-PAN membrane showed obvious fluorescent effect even the mass ratio of PEANI to acrylonitrile was only 0.1 %, which has broken through the traditional limitation of using the cationic dye involved in the dyeing procedure to obtain fluorescent acrylic fabrics.