Abstract: This study aimed to investigate the effect of varying pyrite (Py) content on copper (Cu) in the presence of different regrinding conditions, which were altered using different types of grinding media: iron, ceramic balls, and their mixture, followed by flotation in the cleaner stage. The flotation performance of rough Cu concentrate can be improved by changing the regrinding conditions based on the Py content. Scanning electron microscopy, X-ray spectrometry, ethylenediaminetetraacetic acid disodium salt extraction, and X-ray photoelectron spectroscopy studies illustrated that when the Py content was high, the use of iron media in regrinding promoted the generation of hydrophilic FeOOH on the surface of Py and improved the Cu grade. The ceramic medium with a low Py content prevented excessive FeOOH from covering the surface of chalcopyrite (Cpy). Electrochemical studies further showed that the galvanic corrosion current of Cpy–Py increased with the addition of Py and became stronger with the participation of iron media.