Attapulgite (AT)-reinforced poly(vinyl alcohol) (PVA) nanocomposite films were prepared by solution-casting technique. The nonisothermal crystallization behaviors of PVA bulk and PVA/AT nanocomposites have been investigated by differential scanning calorimetry (DSC). It has been found that the uniformly dispersed AT nanorods in the matrix have great influence on the glass transition temperature and crystallization behavior of PVA matrix. The Jeziorny method has been employed to analyze the DSC data. The results show that Jeziorny method could describe this system very well. Comparing with the PVA bulk, PVA/AT nanocomposites have higher crystallinity X-t, shorter semicrystallization time t(1/2), and higher crystallization rate constant Z(c). It can be concluded that AT can be used as an effective nucleating agent and has effects on the growth of crystallites in the crystallization process of PVA matrix. (c) 2005 Wiley Periodicals, Inc.