We report on the dielectric properties of Zn1-xMnxSe(0≤x≤0.78) epilayers, by capacitance and dissipation factor measurements at temperature 5 K<T<475 K and frequency 20 Hz<f <100 kHz. A Debye-like relaxational contribution to the dielectric response is observed, which requires the presence of charge redistribution. The relaxation is found to be a thermally activated process, and the activation energies obtained from the dissipation factor and capacitance are in good agreement. The capacitance is found to increase with a decrease in test frequency. From our results it is established that the dielectric response is caused by carrier hopping among structural defects. A monotonic variation is found in the relationship between the activation energy and the Mn concentration. This monotonic variation is interpreted in terms of the four-center model, in which the number of Mn atoms appearing in the nearest-neighbor sites of the defect can have four possible configurations. The measured defect behavior reflects the overall average of all energy levels involved in the center, and the result is weighted by the relative concentrations.