Experimental research to clarify the relation between cutting edge geometry and plastic sliding on a four-fluted end mill is performed. Also, an edge, which can reduce dimensional inaccuracy and surface profile error in the finishing process of end milling, is presented. The performance of a newly performed cutting edge is verified through the measurement of chip geometry and cutting force variation in the face milling. It is shown that the sum of the rubbing and ploughing forces can be reduced by making the edge sharp as well as the margin width small. Both surface profile error and surface roughness can be improved in the case where the margin face is polished and protected from the flank wear by TiN coating. It is expected that a finer finished work surface can be derived by polishing the rake face along with the margin face.