The thermal behavior of polyacetylacetonatozirconium (PAZ) was characterized by thermogravimetry-differential thermal analysis-derivative thermalgravimetric (TG-DTA-DTG) techniques. The thermal decomposition studies under air, N-2 flux and N-2 flux after pretreated by steam showed different thermal behavior modes. Further investigation revealed that the steam pretreatment had extraordinarily significant effects on the thermal behaviors of PAZ. X-ray powder diffraction (XRPD) and Fourier transform infrared spectroscopy (FT-IR) were used to indicate the morphology form and confirm the composition of PAZ during the heat-treatment. (C) 2008 Elsevier B.V. All rights reserved.