A rotating electric machine comprising: a first rotor being supported by a plurality of bearings (B3, B4) in a rotatable manner around an axis (Ax), the first rotor having an inner circumference in which a space is formed; a second rotor being supported by a plurality of bearings (B5, B6) in a rotatable manner relative to the first rotor while being arranged coaxially with the first rotor in the space of the inner circumference of the first rotor, the second rotor having coils; and. an electric power transmission unit (25, 25, 25) having at least one rotating member which rotates integrally with the second rotor by being connected electrically with the coils, and connecting a predetermined connection object fixed in an unrotatable manner and the coils, wherein a space is formed in an inner circumference of the second rotor, and at least a part of the power transmission unit (25, 25, 25) is arranged in the space of the inner circumference of the second rotor; the rotating electric machine being characterized in that both of the plurality of bearings (B3, B4) supporting the first rotor and the plurality of bearings (B5, B6) supporting the second rotor include a large diameter bearing (B3, B6) having an internal diameter which is larger than size of the power transmission unit (25, 25, 25) with respect to a radial direction, and the large diameter bearing supporting the second rotor permits the second rotor to rotate relative to the first rotor and is arranged outside the electric power transmission unit (25, 25, 25) with respect to the radial direction. a first rotor being supported by a plurality of bearings (B3, B4) in a rotatable manner around an axis (Ax), the first rotor having an inner circumference in which a space is formed; a second rotor being supported by a plurality of bearings (B5, B6) in a rotatable manner relative to the first rotor while being arranged coaxially with the first rotor in the space of the inner circumference of the first rotor, the second rotor having coils; and. an electric power transmission unit (25, 25, 25) having at least one rotating member which rotates integrally with the second rotor by being connected electrically with the coils, and connecting a predetermined connection object fixed in an unrotatable manner and the coils, wherein a space is formed in an inner circumference of the second rotor, and at least a part of the power transmission unit (25, 25, 25) is arranged in the space of the inner circumference of the second rotor; the rotating electric machine being characterized in that both of the plurality of bearings (B3, B4) supporting the first rotor and the plurality of bearings (B5, B6) supporting the second rotor include a large diameter bearing (B3, B6) having an internal diameter which is larger than size of the power transmission unit (25, 25, 25) with respect to a radial direction, and the large diameter bearing supporting the second rotor permits the second rotor to rotate relative to the first rotor and is arranged outside the electric power transmission unit (25, 25, 25) with respect to the radial direction.. an electric power transmission unit (25, 25, 25) having at least one rotating member which rotates integrally with the second rotor by being connected electrically with the coils, and connecting a predetermined connection object fixed in an unrotatable manner and the coils, wherein a space is formed in an inner circumference of the second rotor, and at least a part of the power transmission unit (25, 25, 25) is arranged in the space of the inner circumference of the second rotor; the rotating electric machine being characterized in that both of the plurality of bearings (B3, B4) supporting the first rotor and the plurality of bearings (B5, B6) supporting the second rotor include a large diameter bearing (B3, B6) having an internal diameter which is larger than size of the power transmission unit (25, 25, 25) with respect to a radial direction, and the large diameter bearing supporting the second rotor permits the second rotor to rotate relative to the first rotor and is arranged outside the electric power transmission unit (25, 25, 25) with respect to the radial direction.