Wire electrochemical micromachining (WECMM) is very useful for fabricating micro-structures without causing tool wear. In WECMM, the accumulation of products can lead to a change in electrolyte conductivity in the small inter-electrode gap, which significantly affects the machining accuracy and efficiency. In this paper, a rotary cutting edge electrode of stainless steel 304 is used as the tool to promote the renewal of electrolyte in the inter-electrode gap and to eliminate dissolution products in machining workpiece of stainless steel 304. The electric field simulation results show that current density distribution changes dynamically as the cutting edge tool rotates. The average current on the side wall is far smaller than when a cylindrical tool is used. The flow field simulation results reveal that only electrolyte in the vicinity of the surface of the tool can be recycled when the cylindrical tool is used, whereas most of the electrolyte in the front gap is involved in the circulation when a cutting edge tool is used. Experiments suggest that the maximum electrode feed rate is improved and the slit width is reduced when a cutting edge tool is used. The cutting edge is helpful to decrease the average current density and accelerate the mass transport process. Finally, a fir tree slot of 5 mm thickness is fabricated by WECMM using a cutting edge electrode at a spindle speed of 15,000 rpm and an electrode feed rate of 2.4 μm/s.