Electrochemical test methods such as cathodic scanning voltammetry and chronoamperometry were used in the acidic system to study the influence mechanism of sodium dodecyl sulfate (SDS) on the electrodeposition process of copper. The results show that the addition of SDS causes the deposition potential to shift positively and reduces the cathodic polarization. When the SDS concentration is lower than the critical micelle concentration of 1g/L, the nucleation relaxation time of copper is prolonged and the nucleation rate is decreased. When the concentration of SDS is higher than the critical micelle concentration, SDS spherical micelles are formed, and the nucleation relaxation time of copper is reduced and the nucleation rate is accelerated. The copper nucleation process conforms to the three-dimensional nucleation/growth mechanism of Scharitker?Hill. When the SDS is 1g/L, in the low overpotential zone of -0.2V, the copper crystals proceed in a progressive nucleation mode at -0.23-0.28V. In the high overpotential zone, the copper crystals proceed in a progressive nucleation mode. When the SDS is 0.5 g/L, copper conforms to the progressive nucleation in the potential region of -0.2V to -0.28V.