1-Amino-2, 4-dinitroimidazole (ADNI) was synthesized by amination of 2, 4-dinitroimidazole with 2, 4, 6-trimethylbenzenesulfonic hydroxylamine (MSH) in a total yield of 57.8%. The structure of ADNI was characterized by IR, ¹H NMR, LC-MS and single crystal X-ray diffraction. Results show that ADNI belongs to orthorhombic system, space group Pca2₁ with a=10.0626(14) Å, b=55.684(8) Å, c=11.5639(15) Å, Z=4, D_c=1.774 g·cm^-3, and DSC test results reveal that ADNI has good thermal stability.