In this paper, a practical micromachining technology was applied for the fabrication of a micro drill using electrochemical etching process. Sodium chloride solution was used as electrolyte, a tungsten carbide rods can be dissolved to some micrometers from original dimension by electrochemical etching with supersonic agitation. High-aspect-ratio of micro tungsten carbide rod was easily obtained by this process. Processing performance was investigated according to applied voltage, etching time, and electrolyte concentration. A micro drill of diameter 60 μm was processed by proposed supersonic aided electrochemical etching process.