Exciton binding energies in Cd1-x Mnx Te/CdTe parabolic quantum well (PQW) with different Mn contents were calculated through variational method in the effective mass approximation. The variations of exciton binding energy as a function of well width, barrier width and electric field were calculated with different Mn compostions. The results show that the exciton binding energy is a non-monotonic function of well width. It increases first until reaching a maximum, and then decreases as the well width increases farther. In addition, with the increase of Mn content the well width should decrease to reach the maximum value of the exciton binding energy due to the change of material band gap. The exciton binding energy increases first until reaching a stable value with the increase of barrier width, which is related to the barrier penetration of wave function. The external electric field has little effect on binding energy, and the effect decreases with the increase of Mn content, but when the electric field is large enough, it will destroy the excitonic effect. The results are meaningful in design of optoelectronic device based on PQW.