1, 1′-Dioxide-5, 5′-azotetrazole dipotassium salt was synthesized via two-step reactions of azido-cyclization and oxidation-coupling using cyanogen bromide, sodium azide and 50% solution of hydroxylamine as raw materials. The yields of two-step reactions were 78% and 82%, respectively. The structure of 1, 1′-dioxide-5, 5′-azotetrazole dipotassium salt was characterized by infrared spectrum (IR), nuclear magnetic resonance (NMR), elemental analysis and thermal properties were studied by differential scanning calorimetry (DSC) and thermogravimetry-derivative thermogravimetry (TG-DTG). Results show that there were two thermal decompositon peaks at 271.0 ℃ and 328.0 ℃ under heating condition, respectively, while possess a total mass loss of 37.5% before 320 ℃ for 1, 1′-dioxide-5, 5′-azotetrazole dipotassium salt.