Abstract: Hydroxylamine perchlorate (HAP) is a new energetic oxidizer. The thermal decomposition of pure HAP and the effects of additives on thermal decomposition of HAP were studied by using TG and DTA in nitrogen atmosphere. The additives are 4 0% NH 4ClO 4, 3 0% HClO 4, and 0 29% FeCl 3 respectively. The TG curves of the above four systems were determined. The experimental results indcate that FeCl 3 has a promoting effect on the decomposition of HAP,but NH 4ClO 4 and HClO 4 have no such effect on the decomposition of HAP. NH 4ClO 4 acts as an inert substance, and HClO 4 has a weak retarding effect on the decomposition of HAP. By using non isothermal TG DTG,the thermal decomposition kinetic equations of the four systems were obtained. Through comparing the kinetic parameters of the four systems,the order of decomposition activation energy ( E ) and reaction order ( n ) were found: HAP+0 29% FeCl 3