A series of novel 1,2,3-benzotriazin-4-one derivatives were designed,synthesized and their inhibitory activities against leulcotriene A_4 hydrolase aminopeptidase in vitro were evaluated.Many compounds showed moderate to good activities at the concentration of 10 μmol/L.Among them,compound Ⅳ-16 exhibited the highest inhibitory activity up to 80.6% with an IC_(50) of 1.30 ± 0.20 μmol/L The compound Ⅳ-16 was also tested the proliferation inhibitory activities in THP1 human AML cell line and its binding model with LTA_4H enzyme by molecular docking was studied.It indicated that 1,2,3-benzotriazin-4-one was a promising scaffold for further study.The relationship between structure and inhibitory activity was also preliminarily discussed. A series of novel 1,2,3-benzotriazin-4-one derivatives were designed, synthesized and their inhibitory activities against leurcotriene A_4 hydrolase aminopeptidase in vitro were .Many Compounds showed moderate to good activities at the concentration of 10 μmol / L. The compounds IV-16 was also tested in the proliferation inhibitory activities in THP1 human AML cell line and its binding model with LTA_4H enzyme by molecular docking was studied. Indicated that 1,2,3-benzotriazin-4-one was promising for further study. The relationship between structure and inhibitory activity was also preliminarily discussed.