Provided is a stator manufacturing method including: inserting a plurality of segment coils into a plurality of slots formed in a stator core; bending arms of the segment coils that protrude from the stator core, in a circumferential direction of the stator core; before or after bending the segment coils in the circumferential direction, directing parallel to each other leading end portions of the segment coils that are adjacent to each other in a radial direction of the stator core; and welding together the leading end portions of the segment coils with the leading end portions directed parallel to each other.