The energetic complex [Cu(pn)₂(FOX-7)₂] (pn=1, 3-diaminopropane) was synthesized by the reaction of K(FOX-7)·H₂O and Cu(NO₃)₂·3H₂O in 1, 3-diaminopropane solution. The thermal decomposition behavior was studied by differential scanning calorimetry (DSC) and thermogravimetry/derivative thermogravimetry (TG/DTG), the specific heat capacity was determined with a micro-DSC and the adiabatic time-to-explosion and the impact sensitivity were studied as well. Results show that the non-isothermal decomposition kinetic equation of the first decomposition process is dα/dT=(10^17.83/β)3α^2/3exp(-1.635×10⁵/RT). The self-accelerating decomposition temperature and critical temperature of t hermal explosion are 145.6 ℃ and 146.7 ℃, respectively. The molar heat capacity is 653.79 J·mol^-1·K^-1 at 298.15 K. Adiabatic time-to-explosion is about 77 s, and the characteristic drop height (H₅₀) of Cu(pn)₂(FOX-7)₂ is 71 cm (>14 J) (RDX, >7.5 J), which indicating Cu(pn)₂(FOX-7)₂ is relatively less sensitive.