The technology for synthesizing 2, 6-diamino-3, 5-dinitropyrazine-l-oxide (LLM-105) was studied by oxidation of 2, 6-diamino-3, 5-dinitropyrazine(ANPZ) on kilogram scale. The yield of LLM-105 is 98.3% and its purity 96.4%. The dosage of trifluoroacetic acid (TFA) is reduced. The structure of LLM-105 was characterized by IR, elemental analysis, ¹H NMR and MS. The recovery technology of TFA mother solution was studied by neutralization, acidification and distillation on kilogram scale. The recovery of TFA is 85.1% and its purity 99.8%. Using the recovery TFA for the oxidation reaction of ANPZ, the yield of LLM-105 can be 97.8%. The factors affecting the oxidation reaction were discussed. The optimum technology parameters of the oxidation reaction are: m(ANPZ):V(H₂O₂)=1:1.8, m(ANPZ): V (TFA) =1:5, reaction temperature 25~30 ℃, reaction time 14 h.The optimum technology parameter of recycling of TFA is m(TFA):V(H₂SO₄)=1:1.0.