A thrust generating apparatus 10 is provided under water and configured to generate thrust by ejecting the water. A rotor main body 43 includes: a first member 48 including a side surface and outer peripheral surface which are opposed to a first water lubricated bearing 40; a second member 49 including a side surface and outer peripheral surface which are opposed to a second water lubricated bearing 41; and a third member 50 including a supporting surface contacting an inner peripheral surface of a rotor core 44. The first to third members 48 to 50 are fixed to one another so that each member is detachable.
