The magnetism of transition metal thin films have been widely studied in the past decades, however, the topology aspect of these traditional materials are not yet investigated.The literatures suggest that relative small perpendicular (with respect to the thin film) inversion symmetry breaking cause giant modication on Magnetocrystalline Anisotropy (MCA), which stems from the special band structure of transition metals.In this taik, I will focus on our latest work on realizing quantum anamolous hall (QAH) state in traditional Fe ultra-thin lm utilizing the inversion symmetry breaking idea.Rather than perpendicular electriceld, we include the substrate effect serving as origin of perpendicular magnetization anisotropy (PMA).Fe/GaAs (ZnSe) junction has been realized experimentally with PMA enhanced compared to bulk, as a result, time reversal symmetry is broken.At the same time, based on a tight-binding band structure calculation, we illustrate that the substrate induced second-order hopping gives rise to topological nontrivial gaps opening in Fe ultra-thin film.From band inversion picture and ective model, we demonstrate the realization of chern insulator in this Fe/GaAs junction system, and chiral edge mode should be observed at certain energy regime.