The Hamiltonian matrices formulae of 5D state for 3d4/3d6 ions in cubic symmetry are derived using a two spin-orbit (SO) coupling parameter model. The Hamiltonian matrices are 25×25(5D) dimensions. On the basis of the formulae, the fine-structure splittings of the ground state in cubic ZnSe∶Fe2+ crystal are calculated. The Zeeman splitting,the Raman shift and the magnetization in magnetic fields up to 30T along the [100] and [111] directions are investigated, respectively. The present results are in excellent agreement with the experimental ones.