A method of manufacturing a stator coil includes the steps of: (1) forming substantially planar electric wires each including in-slot portions to be received in slots of a stator core and turn portions to be located outside of the slots to connect the in-slot portions; (2) rolling each of the planar electric wires into a spiral shape by plastically deforming the turn portions; and (3) assembling the rolled electric wires through relative axial movements therebetween, each of the relative axial movements being made by axially moving first and second components relative to each other with both the first and second components radially elastically deformed and with each of the first and second components circumferentially positioned by at least one positioning member, each of the first and second components being one of the rolled electric wires or an electric wire sub-assembly comprised of a plurality of the rolled electric wires.