Thermogravimetry (TG), differential thermal analysis (DTA), and differential scanning calorimetry (DSC) have been used to examine the thermal behavior of Sn+KClO(3), Sn+KNO(3), and Sn+KClO(4) pyrotechnic systems and the results were compared with thermal characteristics of individual constituents. TG curves for tin powder, heated alone in air, showed a relatively slow oxidation above 570 degrees C. From thermal results the decomposition temperatures of KClO(3), KClO(4), and KNO(3), in nitrogen atmosphere, were measured at 472, 592 and 700 degrees C, respectively. For the Sn+KNO(3) pyrotechnic system, the tin oxidation was completed within the range of 480 to 500 degrees C. Replacing KNO(3) with KClO(4) led to an increase of thermal stability of the pyrotechnic mixture. Among above-mentioned pyrotechnic mixtures, Sn+KClO(3) has the lowest ignition temperature at about 390 degrees C. The apparent activation energy (E), Delta G(#), Delta H(#) and Delta S(#) of the combustion processes were obtained from the DSC experiments. Based on these kinetic data and ignition temperatures, the relative reactivity of these mixtures was found to obey in the following order: Sn+KClO(3) > Sn+KNO(3) > Sn+KClO(4).