The standard (p°=0.1 MPa) molar enthalpies of formation for liquid 1-ethylimidazole and 1-ethylpyrazole were derived from the standard molar enthalpies of combustion ΔcHm°, in oxygen, atT=298.15 K, measured by static bomb combustion calorimetry. The molar heat capacities of both liquids were measured in the temperature range (280 to 365 ) K by differential scanning calorimetry. The standard molar enthalpies of vaporization ΔglHm°, at the temperatureT=298.15 K were measured by Calvet microcalorimetry. The derived standard molar enthalpies of formation in the gaseous state are compared.