A stator includes a hollow cylindrical stator core comprised of a plurality of stator core segments, a stator coil mounted on the stator core, and an outer cylinder that is fitted on the radially outer surfaces of the stator core segments so as to fasten the stator core segments together. The stator core has a recess formed in the radially outer surface of one of the stator core segments. The outer cylinder has a slit that radially penetrates the outer cylinder to connect the radially outer and inner surfaces of the outer cylinder and an engaging portion that adjoins the slit. The engaging portion of the outer cylinder is plastically deformed radially inward into the recess of the stator core so as to abut and thereby engage with side walls of the recess which face the engaging portion.