This study investigates an AlTiNiFeCr alloy with an equiatomic composition, focusing on its microstructure, anodizing, and corrosion behavior in simulated acid rain solution. The AlTiNiFeCr alloy was prepared by vacuum arc melting; the microstructure was examined by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The as-cast alloy was anodized by cyclic voltammetry in 1 M Na2SO4. The anodic oxide film surface morphology was analyzed by atomic force microscope. The corrosion behaviors were studied using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and Mott-Schottky analysis in simulated acid rain solutions. The as-cast AlTiNiFeCr alloy exhibits a multiphase dendritic microstructure with a predominantly face-centered cubic (FCC) structure, body-centered cubic (BCC) structure, and Laves phase. The porous anodic oxide film formed on the AlTiNiFeCr alloy surface after anodizing. Local defective passive film induced the change of passivation of the alloy. A low scan rate (50 mV/s) anodizing by cyclic voltammetry induces the transformation of a p-n-type semiconductor to a p-type semiconductor and thereby improves the corrosion resistance. Copyright © 2025. Published by Elsevier B.V.