Time-resolved photoluminescence has been studied on molecular beam epitaxy grown Cd1-xMnxTe epilayers and Cd1-xMnxTe/Cd1-yMgyTe single-and multiple-quantum wells. The formation of exciton magnetic polarons is detected in the single-quantum wells of various well widths. The transient photoluminescence of magnetic polarons is significantly affected by the external field. The photoluminescence intensity of the exciton is found to show two-exponential decay characteristics. The magnetic field dependence of the two decay times is attributed to the conversion of the dark excitons to the bright excitons by a spin-flip process. The temperature dependence of exciton decay times is interpreted as the thermal activation process in the multiple-quantum well.