In this research, white dextrin as a new, low-cost, and eco-friendly inhibitor was used in 0.05 M NaOH electrolyte for investigating the corrosion behavior of Al1050 alloy. Dextrin contains many OH functional groups to be a proper candidate for adsorbing on the metallic surface. To study this behavior, potentiodynamic polarization (PDP), electrochemical impedance spectroscopy, and weight loss tests were utilized. Furthermore, to evaluate the topography of the surface, atomic force microscopy, and scanning electron microscopy were also used. PDP result tests showed that the highest inhibition efficiency for dextrin was about 97% at ambient temperature in the presence of 1 g/L dextrin. By increasing the test temperature from 298 to 328 K the inhibition efficiency was reduced from 97% to 49% indicating the physical adsorption of dextrin at the metal surface. Results of weight loss tests displayed that the inhibition efficiency decreased up to 40% after 48 h. The surface analysis showed that based on the presence of dextrin, the smoothness of the corroded surface increased about by 64% compared to the uninhibited surface. The obtained results confirmed that the adsorption mechanism of dextrin was obeyed from Langmuir isotherm.