The present work reports the values of the standard (p∘=0.1MPa) molar enthalpies of formation, in the crystalline phase, of 2-trichloroacetylpyrrole and 2-trifluoroacetylpyrrole, which were derived from the standard molar energies of combustion, in oxygen, to yield HCl·600H 2 O(l) and HF·10H 2 O(l), respectively, as well as CO 2 (g) and N 2 (g), at T=298.15K, measured by rotating bomb combustion calorimetry. The values of the standard molar enthalpies of sublimation, at T=298.15K, derived from the Knudsen mass-loss effusion technique are also presented. From the above mentioned experimental quantities, the standard molar enthalpies of formation, in the gaseous phase, were derived: ΔfHm∘(2-trichloroacetylpyrrole, g)=−(102.5±1.6)kJ·mol −1 and ΔfHm∘(2-trifluoroacetylpyrrole, g)=−(704.7±3.0)kJ·mol −1 . These experimental values are compared with estimates based on high-level ab initio molecular orbital calculations at the G3(MP2)//B3LYP level, which have also been extended to the calculation of other thermodynamic properties namely N–H bond dissociation enthalpies, gas-phase acidities and basicities, proton affinities, and adiabatic ionization enthalpies.