Abstract: Electrochemical corrosion behaviors of carbon steel, galvanized steel and pure copper in water-saturated acid red soil were studied by room-temperature corrosion test and electrochemical test. The results show that with increasing corrosion time, the average corrosion rates of the carbon steel and galvanized steel decreased, and the average corrosion rate of the pure copper increased slightly. During corrosion in water-saturated red soil for 45 d, the carbon steel had the highest average corrosion rate followed by the galvanized steel. Non-uniform overall corrosion morphology was observed on the carbon steel and galvanized steel surfaces, and uniform corrosion morphology was observed on the pure copper surface. The electrochemical impedance spectra of the carbon steel, galvanized steel and pure copper all showed double capacitive loops with 2 time constants. Warburg impedance appeared in the low frequency zone of impedance spectra when the carbon steel, galvanized steel and pure copper were corroded for 30, 45, 20 d, respectively. The corrosion reaction control mode changed from the charge transfer process to the combination of the charge transfer and diffusion processes.