The purpose of this work was to improve the properties of the starch/poly(vinyl alcohol) (PVA) films with nano silicon dioxide (nano SiO2). Starch/PVA/nano-SiO2 biodegradable blend films were prepared by a solution casting method. The characteristics of the films were assessed by Fourier Transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The results obtained in this study indicated that the nano-SiO2, particles were dispersed evenly within the starch/PVA coating and an intermolecular hydrogen bond and a strong chemical bond C-O-Si were formed in the nano-SiO2, and starch/PVA. That the blending of starch, F)VA and nano-SiO, particles led to uniform starch/PVA/nano-SiO2, blend films with better mechanical properties. In addition, the nano-SiO, particles can improve the water resistance and light transmission of the blend films. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 113: 34-40, 2009