Abstract: Diamond-like carbon(DLC) film composed of macroscopically in sulating but microscopically a mixture of conducting(sp²) and insulating(sp³) phases was locally electrically mod ified by using conductive atomic force microscope(AFM).Especially topography change was observed when DC bias voltage lies applied.The results sh ow that the DLC surface is not modifie dafter direct current is applied on the tip.While positive voltage is applied on DLC surface,nanoscale crater on surface is formed.According to the interaction force between CoCr MESP tip and DLC surface,the "scalewing effect" occurring in the crater is explained.Electromechanical coupling on DLC film indicates that the depth of crater increases with the augment of force applied on surface when norm al pressure is less than a certain threshold value.Therefore,DLC film is asuitable recording med ia for high-density recording devicesusing pit-recording techni que because of its excellent mechani cal properties.