Abstract: The study of the exotic structure of nuclei in the island of inversion has always been a hot topic in modern nuclear physics. In this paper, we apply the Complex Momentum Representation(CMR) method to study the resonant states of nuclei. We calculate the single particle bound and resonant energies of ³³Mg and their variation with the deformation parameter β₂. The occupancy probabilities of the main configurations are tested at the energy level occupied by the last valence neutron and the radial density distributions are calculated. The results show that the ground state of ³³Mg has undergone a p-f inversion of the single particle level, and its last valence neutron occupies the intruder energy level. Meanwhile, the deformation range of ³³Mg is about 0.49≤β₂≤0.55, which is similar to the deformation values of isotopes around ³³Mg.