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Higher order topological insulator (HOTI) is a novel quantum topological phase with gapless states along the hinges of a crystal. Despite theoretical predictions in several potential materials, enough experimental studies on crystalline HOTI materials is still lacking. The interplay of magnetism and topology has been shown to give rise to various magnetic topological states, including axion insulator and HOTI states. In this talk, we will present a systematic study on the electronic structure of EuIn₂As₂ and its evolution across the antiferromagnetic transition below 16 K by utilizing high-resolution angle-resolved photoemission spectroscopy combined with parallel first-principles computation. The antiferromagnetic EuIn₂As₂ has been predicted to host both the axion and the HOTI states. We directly observe the linearly dispersing hole-like bands crossing the Fermi level and the change in their dispersion across the magnetic phase transition. Our study points to EuIn₂As₂ as being a promising material to explore interplay between topology and magnetism.