Membranes of poly vinyl alcohol (PVA)/silica functionalized with mercapto groups are synthesized by electrospinning. Scanning electron microscopy (SEM) studies showed that the fiber diameters are in the range of 200-300 nm. The thickness of nanofiber decreases with an increase in calcination temperature. The results of Fourier transform infrared (FTIR) indicated that PVA/silica nanofibers are functionalized by mercapto groups via the hydrolysis poly-condensation method. N(2) adsorption-desorption showed that organic molecules can be removed completely when the PVA/silica composite fibers are calcinated at 800 degrees C. The fibers calcinated at 800 degrees C were pure inorganic silica species with a mesoporous structure. These mercapto groups functionalized PVA/silica nanofibers have a great potential application in the field of. adsorption of heavy metal ions. (C) 2010 Published by Elsevier B.V.