In this study, an atomic absorption spectrophotometric method is presented for the determination of calcium stearate in polymer samples after their pyrolysis. Samples of polymers were burned in an electrical furnace at 500 degrees C. After thermal degradation of polymeric matrix, 1M HCl solution was added to dissolve the residue. Then the absorbance of solution was measured by an atomic absorption spectrophotometer at calcium atomic line. This method has an extent linear dynamic range (0.4-50 mg/L) with a limit of detection (LOD) 0.1 mg/L in solution. LOD of the proposed method in polymer sample using 0.5 g sample size is 15 ppm as calcium stearate. Some effective parameters such as time and temperature of pyrolysis and concentration of hydrochloric acid were studied. Finally, this method was successfully applied for the determination of calcium stearate content of standard and real polymers. (c) 2008 Wiley Periodicals, Inc.