Each of the mixtures exhibits only the nematic phase with a similar temperature range. Both the mixtures contain phenyl cyclohexane and cyclohexane carboxylate groups. However, mixture 1 contains biphenyl cyclohexane, whereas mixture 2 contains cyano cyclohexane. Until now, no systematic study on the two mixtures have been reported. Our interest is to compare the macroscopic properties of the two mesogenic mixtures and to study the effect of replacing the biphenyl cyclohexane group in mixture 1 by a cyano cyclohexane group in mixture 2. With this aim, the variation of the dielectric permittivities epsilon(perpendicular to) and epsilon(vertical bar vertical bar) with temperature has been determined for both the samples in an aligning magnetic field at frequencies of 1 kHz, 10 kHz, and 100 kHz, and the dielectric properties of the two mixtures have been compared. We have also calculated the variation. of angle of inclination beta of the molecular dipole moment with the director for both the samples as a function of temperature.