A stator includes an annular stator core, a stator winding, and an insulating sheet member. In the stator core, slots are circumferentially arrayed. The stator winding includes conductor segments having oblique portions formed by open end portions being circumferentially twisted. The open end portions are inserted into the slots from one of two axial-direction sides and extend towards another one. The insulating sheet member is interposed between an inner wall surface of the slot and the conductor segment. The insulating sheet member is rolled into a cylindrical shape along the inner wall surface of the slot, and includes an overlapping portion and a slack portion. In the overlapping portion, two circumferential-direction end portions overlap each other. The overlapping portion is disposed on one of two radial-direction sides of each of the slots. The slack portion is disposed on another one of two radial-direction sides of each of the slots.