Abstract: A stator of a submerged motor is provided with cylinders formed of carbon fiber reinforced plastics of superhigh precision. To obtain flawless joints between the cylinders of carbon fiber reinforced plastics and the end covers increased wall thickness portions are provided at opposite axial end portions of an inner cylinder near joints of the inner cylinder with the end covers, one increased wall thickness portion being located at one axial end portion on an outer side surface thereof and the other increased wall thickness portion being located at the other axial end portion on an inner side surface thereof. Thus, the inner cylinder has a small wall thickness at an axial central portion to reduce an eddy current loss while its wall thickness is increased at the opposite axial end portions to improve mechanical strength and facilitate joining of the end covers to the inner cylinder.