The inhibition performance of domperidone on the corrosion of copper in different concentration of HCl solution has been investigated by electrochemical, weight loss, and surface analysis, and theoretical calculation methods. Results indicate that domperidone was found to be an effective inhibitor with the inhibition efficiency as high as 98.5% when the HCl concentration was 0.01M, and the corrosion rate of copper increased with the increment of HCl concentration from 0.001 to 1M. The potentiodynamic polarization results revealed that domperidone can be seen as a mixed type inhibitor when the HCl concentration was high (1 and 0.1M), while it acted as a cathodic inhibitor for copper at low HCl concentrations (0.01 and 0.001M). The potentiodynamic polarization results revealed that domperidone can be seen as mixed-type or cathodic inhibitor as the HCl concentration changes. Scanning electron microscopy studies indicated the formation of protective films of inhibitor molecule on copper surface. Besides, density functional theory-based quantum chemical calculations and molecular dynamics simulations showed the electronic structure of domperidone and its optimized adsorption configuration on copper surface, which could account for the experimental findings.