Following our recent study on triazane, we present a follow-up study on the thermodynamic properties of triazane’s unsaturated analog, triazene. We predict optimized structural parameters, vibrational frequencies, enthalpies of formation, enthalpies of combustion, specific enthalpies of combustion, and proton affinities. Our results indicate that the cis form of triazene has a specific enthalpy of combustion of −15.2 kJ g−1 and the trans form has a specific enthalpy of combustion of −14.7 kJ g−1.