1-Diazidecarbonimidoyl-5-azidotetrazole(DACAT) was prepared via diazotized substitution reaction and cyclization reaction using triaminoguanidinium as raw material.Its structure was confirmed by IR, ¹³C NMR and ¹⁴N NMR.The influence of triaminoguanidinium/sodium nitrite molar ratio, reaction temperature, reaction time and pH of system on the yield of reaction was examined.The geometry of DACAT were optimized at the B3LYP/6-31G(d, p) basis set level using a density functional theory(DFT) Theoretical density(ρ), enthalpy of formation of gas phaseΔ_fH_{g, m}^θ, enthalpy of formation of solid phaseΔ_fH_{s, m}^θ, detonation velocity(D) and detonation pressure(p) for DACAT were calculated by Monte-Carlo method, complete base set method(CBS-4M) and Kamlet-Jacobs formula, respectively.Results show that the optimized process conditions were determined as:n(triaminoguanidinium):n(sodium nitrite)=1:2, diazotized substitution reaction temperature 0 ℃, cyclization reaction temperature 20 ℃, pH=8.0, diazotization reaction time 30 min and cyclization reaction time 30 min.The total yield of the two steps reactions was 12.6%.The obtained values of ρ, Δ_fH_{g, m}^θ, Δ_fH_{s, m}^θ, D and p are 1.7628 g·cm^-3, 1590.42 kJ·mol^-1, 1435.44 kJ·mol^-1, 8725 m·s^-1 and 34.52 GPa, respectively.