New energetic materials with molecular perovskite structure (H₂dabco[NH₄(ClO₄)₃](DAP, dabco =N(CH₂CH₂)₃N) were prepared from ammonium perchlorate, 1, 4-diazoxane[2.2.2]octane and perchloricacid, and its crystal structure and morphology were characterized by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy(EDS). The thermal decomposition properties of the DAP and AP were studied by thermo gravimetric (TG) and differential scanning calorimetry (DSC). And the hygroscopicity of DAP and AP was measured by weight gain method. Results show that DAP is a new crystal different from AP in structure and morphology. It exhibited the exothermic peak temperature of 385 ℃ and apparent decomposition heat of 3157 J·g^-1.Compared with the AP after the recrystallization, the exothermic peak temperature delayed 19 ℃, apparent decomposition heat increased by 2221.9 J·g^-1. The hygroscopicity of AP is determined to be 0.560%, while the hygroscopicity of (H₂dabco)[NH₄(ClO₄)₃] is only 0.044%, indicating that this method effectively reduce the hygroscopicity of AP.