Direct nitrolysis of hexamethylenetetramine(HA) catalyzed by ionic liquids (ILs) was studied. The effects of dosage of IL and different ILs on the nitrolysis were investigated in the systems of 95% HNO₃ and N₂O₅/HNO₃.In the system of 95%HNO₃,［Hmim］NO₃ shows the best catalytic activity in all of ILs we screened. The optimal reaction condition is 1.5mol% IL loading,12：1 of quality ratio of 95% HNO₃ to HA and 90 min of reaction time at -5~0 ℃. RDX can be obtained in yield of 75.9% using IL as catalyst under optimized condition,while RDX can be gererated in lower yield of 68.3% without adding IL. In the system of N₂O₅/HNO₃,［Bmim］BF₄ shows the best catalytic activity. The optimal reaction conditions are 5mol% IL loading,9：1 of mass ratio of 100% HNO₃ to HA,2：1 of quality ratio of 100% HA to N₂O₅ and 60 min of reaction time at -5~0 ℃. Under optimized conditions,77.6% yield of RDX can be obtained without adding IL,while yield of RDX can be improved to 85.4% using IL as catalyst. It indicates that ILs have observably catalytic activity on the direct nitrolysis of HA.