A combination of Fabry-Pérot interferometry i.e. white light-optical interferometry and the DC electrochemical method have been used for the first time in situ to measure the aluminum oxide film thickness and anodic current density of aluminum oxide films in 06 and 10% sulfuric acid solutions (H2SO4). The calculated values of the anodic current density by Fabry-Pérot interferometry were verified by the DC electrochemical method and the electrochemical impedance spectroscopy (EIS). The corresponding thickness of the aluminum oxide film to the anodic current density was determined by Fabry-Pérot interferometry under a potentiostatic potential of 9 V with respect to the open circuit potential of the aluminum samples in the H2SO4 solutions for 90 minutes. The obtained thickness of the aluminum samples by Fabry-Pérot interferometry was verified by scanning electron microscopy(SEM) and compared to values that were obtained by the EIS. The calculated anodic current density by Fabry-Pérot interferometry was found in agreement with those of the DC electrochemical method. In contrast the calculated anodic current density by Fabry-Pérot interferometry was found in a slight discrepancy with data obtained by the EIS.Keywords. Aluminum Aluminum oxide film Fabry-Pérot interferometry Electrochemical impedance spectroscopy (EIS) Anodic current density and Sulfuric acid.