A magnetic rotating motor generator of the present invention comprises a rotating portion which is made of a non-magnetic substance whose periphery is provided with a group of permanent magnets tilted at a predetermined angle in an embedded manner ; a group of electromagnets that are disposed adjacently to the rotating portion so as to oppose the group of permanent magnets ; a positional sensor for detecting positions of the group of permanent magnets ; a controller for applying an electric current to the electromagnet on the basis of a detected signal from the positional sensor ; and a power generating section for obtaining power from a coil of the electromagnet. A rotation mode and a power generation mode are repeated, so that power generation is performed while a function as a motor is exhibited.