The azeotropic data of the cyclohexane + 2-propanol + ethyl acetate + butanone quaternary system were measured by using a stainless steel azeotrope apparatus developed by the authors at elevated pressures of 101.3, 302.0, 502.0, 702.0, and 902.0 kPa and predicted by using the Wilson and NRTL activity coefficient models with the paired energy parameters obtained from binary azeotropic data of the six corresponding systems. The calculated results demonstrate that the predicted data are in good agreement with the experimental, and the Wilson and NRTL equations are of comparable accuracy in the prediction of azeotropes for this miscible quaternary system at elevated pressures.