Thermal and explosion characteristics of ring(menu) substituted arylammonium perehlorates (RSAP) are studied by IYI'A, impact and friction sensitivity measurements. Exothermie decomposition temperature (Td) from DTA curves and impact sensitivity data (hso~) were found to be linearly related to the Hammett substituent constant (e+,cr -) and pK, values of the corresponding arylamines. A reaction scheme, based on the formation of reaction intermediates during decomposition and explosion, accounting for the products, is proposed which, involves proton transfer as the rate determining process and evolution of ammonia. It seems that oxidation-reduction reactions between the arylamine/substituted benzene and HCIO4 or its decomposition products cause explosion.