Vapor-liquid equilibrium (VLE) measurements are reported for the binary systems n-decane + (-)-menthone and n-decane + (+)-fenchone at the constant pressure of 6666 Pa in the temperature range from 344.45 to 390.75 K. The boiling temperatures of the mixtures were also measured at seven constant compositions in the pressure range from 2319 to 16578 Pa. The experimental data were found to be thermodynamic ally consistent. Reduction of the VLE data was carried out by means of Wilson, NRTL and UNIQUAC equations.