Based on energetic compound [1,2,5]‐oxadiazolo‐[3,4‐d]‐pyridazine, a series of functionalized derivatives were designed and first reported. Afterwards, the relationship between their structure and performance was systematically explored by density functional theory at B3LYP/6‐311 g (d, p) level. Results show that the bond dissociation energies of the weakest bond (N–O bond) vary from 157.530 to 189.411 kJ · mol−1. The bond dissociation energies of these compounds are superior to that of HMX (N–NO2, 154.905 kJ · mol−1). In addition, H1, H2, H4, I2, I3, C1, C2, and D1 possess high density (1.818–1.997 g · cm−3) and good detonation performance (detonation velocities, 8.29–9.46 km · s−1; detonation pressures, 30.87–42.12 GPa), which may be potential explosives compared with RDX (8.81 km · s−1, 34.47 GPa ) and HMX (9.19 km · s−1, 38.45 GPa). Finally, allowing for the explosive performance and molecular stability, three compounds may be suggested as good potential candidates for high‐energy density materials. Copyright © 2016 John Wiley & Sons, Ltd.