A simple method, requiring the characterization factor as the only input, is proposed to predict the enthalpies of the liquid and vapor petroleum fractions over a wide range of temperatures and pressures. This method showed a comparable accuracy in the prediction of the petroleum fraction enthalpy with much more complicated predictive methods in the literature. The proposed method gave overall deviations of +/-2.48% when tested on the data for liquid fractions and +/-1.23% when tested on the data for vapor fractions.