The single crystal structure of 4-amino-1, 2, 4-triazole NTO salt ((AT)(NTO)) prepared by neutral reaction of 4-amino-1, 2, 4-triazole (4-AT) and NTO was determined by a four-circel X-ray diffractometer. The results show that the crystal is moloclinic, space group P_21/c with main crystallography parameters a=7.071(2) Å, b=6.361(3) Å, c=18.792(7) Å, β=96.43(3)°, V=839.9(5) ų, Z=4, D_c=1.694 g·cm^-3, μ=0.145/mm, F(000)=440. The atoms of the 4-AT cation and the atom of the NTO anion in (AT)(NTO) crystal are in a plane of self-triazole ring. The two plane angle is 7.6°. The values of standard volume of gas evlved by 100 ℃/48 h, 50% drop height of impact sensitivity, explosion probability of friction sensitivity, 50% fire voltage and 50% fire energy by vacuum stability test(VST) and sensivity tests to impact, friction and static electricity spark are 0.28 mL·g^-1, 124.7 cm, 0%, 12.841 kV and 2.515 J, respectively, indicating that (AT)(NTO) is thermally stable and insensitive to impact, friction and spark.