An alternator has stator winding including a number of stator winding sub-portions each of which is constituted by insulated strands of wire wound onto the stator core so as to be housed in different layers relative to a slot depth direction within slots a predetermined number of slots apart, the different layers within the slots the predetermined number of slots apart being joined in series outside the slots to constitute coil ends; each of the coil ends is formed into a connection pattern comprising a pair of root portions extending outwards from the slots the predetermined number of slots apart, a pair of inclined portions bent over and extending circumferentially from the root portions and a connecting portion connecting ends of the pair of inclined portions to each other; coil end groups of the stator winding are constructed by arranging the coil ends formed into the connection pattern neatly into rows circumferentially at both axial ends of the stator core, and the coil ends in at least one of the coil end groups are arranged in rows circumferentially such that the inclined portions of adjacent coil ends are in close proximity to each other without gaps.