Method for manufacturing end mill

A method for manufacturing an end mill in which a tip portion of a tool body includes three or more odd number of gashes to define three or more odd number of end cutting edges such that one of the odd number of end cutting edges is configured to reach a rotation center while the other end cutting edges are configured not to reach the rotation center, wherein in adjusting a tilt angle in a depth direction and/or an opening angle in a radial direction of the gash provided corresponding to each of the end cutting edges to cause a center of gravity of the tool body to approach a rotation axis by adjusting a size of the gash provided corresponding to each of the end cutting edges, the tilt angle in the depth direction and/or the opening angle in the radial direction of the gash defining the end cutting edge located rearward in a rotation direction of the end cutting edge configured to reach the rotation center is made larger than the tilt angle and/or the opening angle of the gash defining the other end cutting edges.