In this study, the aliphatic polyketone (PK) fibrous membrane was successfully prepared from the solution by electrospinning process at room temperature. As solvents for PK polymer, the mixed solvents of trifluoroacetic acid (TFA) and dichloromethane (MC) were used. Electrospun PK fibrous membrane was characterized by scanning electron microscope (SEM), wide angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), Fourier transform infrared spectrophotometer (FT-IR), and Raman spectroscopy, and compared to the corresponding cast PK film. The crystal structures of electrospun PK fiber and solvent cast PK film were characterized by WAXD. The result indicated that the crystal structure of cast PK film was assigned to a-form, while the crystal structure of PK fibrous membrane corresponded to beta-form, which was attributed to fast crystallization during electrospinning process. Accordingly, the crystallinity of electrospun PK fibrous membrane was lower than that of solvent cast PK film. To confirm further these crystalline structures, FT-IR and Raman spectroscopy were employed. (C) 2010 Elsevier Ltd. All rights reserved.