Sodium tetra(5-nitrotetrazolate) diaquate ferrate(Ⅱ) (NaFeNT) was synthesized from sodium 5-nitrotetrazolate ferrous chloride with temperature 98-100 ℃ and circumfluence time 3 h. The color of crystal is orange. The structure was characterized by elemental analysis, scanning electron microscopy, energy dispersive spectrometry, and Fourier transform infrared. The thermal properties (DSC, explosive temperature), stability properties (hygroscopicity, vacuum stability), explosive properties (explosion heat, specific volume, detonation velocity, impact, friction, flame, electrostatic spark sensitivity) and wastewater treatment method were studied. The results show that the thermal decomposition peak of NaFeNT is 258 ℃ and 5 s explosive temperature is 278 ℃. The hygroscopicity capacity is 3.58% under 30 ℃/120 h and decomposition gas capacity is 0.17 mL·g^-1 under 100 ℃/ 40 h/vacuum. Explosion heat, detonation velocity and specific volume are 3929 J·g^-1, 5550 m·s^-1, 506 mL·g^-1, respectively. NaFeNT is insensitive to impact, electrostatic spark and sensitive to friction. Its flame sensitivity is 76% with 2 cm.