Up to now, the energy, spin and parity of the energy levels of Mg24 below 5.24 Mev. have been precisely measured, but those above it are far less accurate. Though the rotational Characteristic of Mg24 levels is well established, yet the discrepancy between the experimental value 4.12 Mev. and the value 4.6 Mev. calculated from the simple rotation energy formula is beyond the limit of experimental uncertainty. There are two kinds of corrections, the rotation-viberation interaction and the rotational perturbation. In this paper, we show that the levels of Mg24 can not be explained satisfactorily by taking into consideration either one of the above mentioned corrections singly. When both of them are taken up simultaneously, the experimental values of the energy levels and spin of Mg24 can be well accounted for and the recently measured γ-transition branching ratio and E(2)/M(1) ratio can also be explained.