Two novel 1, 2, 3-triazine compounds-6-nitrobenzene[3, 4-e]-1, 2, 3-triazine-4(1H)-oxime and pyrazole[3, 4-e]-1, 2, 3-triazine-4(1H)-oxime were prepared using 2-cyano-4-nitroaniline and 3-amino-4-cyanopyrazole as starting materials via the reactions of oxime and diazotization. The structures of intermediates and target compounds were characterized by means of IR, ¹H NMR, ¹³C NMR, elemental analysis and MS. The influences of different factors on the yield of oxime were studied. The suitable synthetical condition of 2-amino oxime-4-nitroaniline were confirmed that the material ratio of 2-cyano-4-nitroaniline and hydrochloric hydroxylamine was 1: 1.20, 80 ℃, pH=10, reaction time 2 h and the yield was 95.6%. The suitable synthetical conditions of 3-amino-4-amino oximepyrazole were that the material ratio of 3-amino-4-cyanopyrazole and hydrochloric hydroxylamine was 1: 1.25, 80 ℃, pH=10, reaction time 2 h and the yield was 79.3%. The reaction mechanism was studied, and the reasons why it occured that the different amino in the reactions of diazotization and elimination were analyzed.