[en] In an appropriate electrochemical environment, the discrete thermal electron emission could be induced in the micro area due to the uneven distribution of electron flux on the anode surface. Thus an oxygen molecule could be ionized at the liquid-solid interface after collision, and then oxygen plasma with distribution characteristics would be formed. The plasma electrolytic oxidation (PEO) could happen at the liquid-solid interface. In this work, the low carbon steel was used to study the deburring process by PEO at a high frequency (70000 Hz) pulse DC mode. Its burr height H from 3.23 mm to 0.04 mm was removed to form a smooth surface within 6 min. The values of corrosion potential and current density for the untreated sample were −0.667 V and 6.735×10⁻⁵ A/cm², respectively. But for the treated sample, the corrosion potential and current density were relatively lower, −0.354 V and 1.19×10⁻⁷ A/cm². Therefore, PEO was expected to be a new deburring method of carbon steel for the material processing field. (paper)