The type of organic additives significantly affects copper electropolishing performance, including glossiness and surface smoothness. Therefore, developing efficient and eco-friendly additives is crucial for advancing this technology. This study investigates the effects of glycerol and ascorbic acid on copper electrochemical properties and surface morphology. Using the Box- Behnken Design (BBD), we examined the interaction effects of polishing time (A), current density (B), and polishing temperature (C) while optimizing the process parameters. The results demonstrate that glycerol and ascorbic acid additives effectively reduce the critical current density and limiting current density, synergistically enhancing copper surface glossiness and smoothness while slowing down the dissolution rate of the copper. Interaction analysis revealed a prioritized sequence of effects: AB > BC > AC. Under optimal conditions (1.5 min of polishing time, 12 A dm −2 of current density, and 27 °C of polishing temperature), copper surface roughness decreases from 1.2 μm to 37 nm, representing a 97% reduction, along with enhanced corrosion resistance.