1-Methyl-3, 4, 5-trinitropyrazole(MTNP) as an insensitive energetic compound was one-step synthesized with 1-methylpyrazole via direct nitration using mixture of nitric acid and fuming sulfuric acid for the first time.The structure of MTNP was characterized by IR, NMR, elemental analysis, and mass spectrum.The reaction conditions were optimized as following:reaction temperature 90 ℃, reaction time 6 h, molar ratio of HNO₃ and fuming sulfuric acid 1:8.At this condition, the yield of MTNP can reach up to 15.2%.Thermal behavior of MTNP was studied by DSC.Results show that its decomposition temperature is 272.0 ℃, indicating a good heat stability.