Abstract: In order to study effects of subsurface morphology and corrosion depth of copper wire on surface quality of enameled wire, the surface corrosion condition and the morphology of copper powder from different batches of Φ2.000 mm copper wires were observed. Copper powder quality, particle number and pinhole number produced during the preparation of Φ0.800 mm enameled wires were statistically analyzed. Results showed that when defects were present on subsurface of copper wire, the number of particles and pinholeson per 10,000 m increased during production of enameled wire. Under the same time of corrosion in nitric acid solution, the corrosion depth of copper wire was directly proportional to the mass of copper powder produced during the preparation of enameled wire, and the increase of copper powder led to the increase of the number of particles and pinholes per 10,000 m of enameled wire.