In the tip section of an end mill body, a plurality of end cutting edges are formed. In the outer peripheral section of the end mill body, a plurality of peripheral cutting edges are formed. Some of the plurality of end cutting edges are long end cutting edges. The angle which is formed by the straight line that connects the axis to a peripheral cutting edge continuous with a long end cutting edge and by the straight line that connects the axis to a peripheral cutting edge continuous with the end cutting edge positioned in forward of the long end cutting edge in the end mill rotation direction, is larger than the angle which is formed by the tangent lines at the inner ends of the long end cutting edge and the end cutting edge positioned in forward of the long end cutting edge in the end mill rotation direction.