<p>The corrosion behavior of 0Ni2Cu6 copper-containing carbon steel in seawater containing sulfate-reducing bacteria (SRB) at different pH was investigated in this study. The corrosion rate, morphology of products, and bactericidal action of copper were tracked by using weight loss tests, scanning electron microscopy, x-ray photoelectron spectroscopy, and electrochemical analysis techniques. It was found that the metabolic growth of SRB increased the pH of the environment, which was finally stabilized at approximately 9.2. The environmental pH influences the type of copper corrosion products formed in copper-containing carbon steel. Due to the greater bactericidal efficacy of Cu²⁺ compared to Cu⁺, in a weakly alkaline environment (pH 9.0), Cl⁻complexes with newly oxidized Cu⁺ to form [CuCl₂]⁻, hindering the conversion of Cu⁺ to Cu²⁺ and weakening the antibacterial and antifouling properties of the steel. In terms of corrosion morphology, the corrosion degree gradually increases with increasing pH, and significant changes in corrosion product morphology occur under weakly alkaline conditions. Electrochemical analysis indicates that the impedance value is negatively correlated with the corrosion rate, and pH changes affect parameters such as charge transfer resistance, thereby altering the corrosion resistance of the material. This study provides a theoretical basis for the protection against microbial corrosion of steel used in marine engineering, facilitates a deeper understanding of the corrosion mechanism of copper-containing carbon steel under the synergistic effect of pH and SRB, and offers a reference direction for the rational application of such steel in marine environments.</p>