New polynitroimidazole explosive molecules were designed using 2,4, 5-trinitroimidazole as “matrix” structural unit. The explosion parameters of designed explosives were calculated by Brinkley-Wilson(B-W)rule for predicting explosion decomposition products, Rothsteine′s method for estimating detonation velocity and Kamlet method for estimating C-J pressure. And the calculated detonation parameters were compared with those of RDX and HMX explosives. Results show that the designed explosives are a new class of high energy density material compounds with high density, detonation velocity and detonation pressure approaching to that of RDX even HMX. As imidazole ring in the molecules, having aromacity, the stability of these explosives molecules designed is favorable for potential application. 