An hypothetical chemical reaction between hydrogen sulfide and monoethanolamine is set up to permit thermodynamic calculations of the partial heats of solution of hydrogen sulfide in aqueous monoethanolamine solutions. The solubility data of hydrogen sulfide in various concentrations of monoethanolamine and water were used to make the calculations. The partial heats of solution of hydrogen sulfide were calculated for 0.6, 1.0, 1.5, 2.0, 3.0, 4.0, and 5.0 normal monoethanolamine solution at 15, 25, 35, 45, 55, and 60 deg. C. at partial pressures of hydrogen sulfide ranging from 25 mm of mercury to 700 mm of mercury. The partial heat cf solution calculate( for the 100 deg. C. isotherms are to be considered a extrapolated values since no experimental solubility data is available at 100 deg. C. The accuracy with which the derived equation represent the solubility data is determined by tabular comparison of the calculated values with the original experimental data. Over the range of conditions studied, the partial heat of solution of hydrogen sulfide is found to vary from -4,000 to -13,000 calories per gram mol of dissolved hydrogen sulfide. The pronounced effect of partial pressure, ethanolamine concentration, and temperature on partial heats of solution of hydrogen sulfide are presented graphically.