The isobaric vapor-liquid equilibrium data for citronellal + geraniol and citronellal + citronellol systems were obtained experimentally at vacuum pressures of 16.0 and 32.0 kPa using a modified glass Othmer still. Gas chromatography was used to analyze the equilibrium samples of liquid- and vapor-phase compositions. The reliability of the experimental data determined in this study was confirmed using the L-W Wisniak and Fredenslund methods. The data were correlated with the Wilson, NRTL, and UNIQUAC equations to obtain the binary parameters, resulting in an average absolute deviation of the temperature of less than 0.5 and a vapor fraction of less than 0.0286. Prediction of the vapor-liquid equilibrium data of related systems was obtained using UNIFAC, giving better results at 16.0 kPa.