A nitrogen-rich energetic compound-triaminoguanidinium 2, 4, 6-trioxo-1, 3, 5-triazinan-1-ide (1) was prepared with a yield of 91% via one-step metathesis reaction using triaminoguanidinium hydrochloride (TAG-HCl) and sodium cyanurate (CANa) as raw materials. The structure of the product was characterized by X-ray single-crystal diffraction, UV-Vis, FT-IR, ¹H NMR, mass spectrometry and elemental analysis. The enthalpy of formation and detonation parameters of the product were calculated. Its thermal stability, non-isothermal reaction kinetics and decomposition process were studied by differential scanning calorimetry(DSC) at a heating rate of 10 K·min^-1 and thermogravimetric (TG) analysis coupled with Fourier transform infrared spectroscopy (FTIR). The impact sensitivity of the product was determined by the drop hammer test. Results show that the crystal of compound 1 is monoclinic, space group P2₁/n with a calculated density of 1.676 g·cm^-3. Its enthalpy of formation is 327.9 kJ mol^-1, the detonation velocity 7900 m·s^-1, and the detonation pressure 26.5 GPa. Probable thermal decomposition mechanism of 1 under N₂ atmosphere as shown in the text is proposed. Compound 1 is very insensitive to impact, and the impact sensitivity is greater than 60 J, which is better than that of TATB (50 J).