2, 6-Diamino-3, 7-dis(nitroimino)-2, 4, 6, 8-tetrazabicyclo[3.3.0] octane, a new energetic compound, was synthesized from 3, 7-bis(nitroimino)-2, 4, 6, 8-tetraazabicyclo[3.3.0]octane and DppONH₂ via neutralization reaction and amination reaction. The structure of 2, 6-diamino-3, 7-dis(nitroimino)-2, 4, 6, 8-tetrazabicyclo[3.3.0] octane was characterized by infrared(IR) spectroscopy, nuclear magnetic resonance(NMR) and mass spectrometer(MS). The factors effecting the yield of target compound was investigated by orthogonal experiment. Results indicates that the yield of 2, 6-diamino-3, 7-dis(nitroimino)-2, 4, 6, 8-tetrazabicyclo[3.3.0] octane is the highest(35.07%) under the conditions of reaction time 48 h, reaction temperature 40 ℃ and 3:1 as mole ratio. The stable geometry of the compound was completely optimized at the B3LYP / 6-31G++(d, p) theoretical level of density functional theory(DFT). The theoretical density of the target compound is 1.73 g·cm^-3 by Monte-Carlo method. The heat of formation is 416.09 kJ·mol^-1 via isodesmic reaction. The detonation velocity and detonation pressure are 8.90 km·s^-1 and 34.27 GPa predicted by Kamlet-Jacobs formula. All the results show that the theoretical density, detonation velocity and detonation pressure are closed to that of RDX.