With a view to attaining a high quality of a diagnostic image there is provided a magnetic resonance imaging apparatus wherein an image is formed on the basis of magnetic resonance signals received from a subject with an electromagnetic wave transmitted thereto in a static magnetic field. The magnetic resonance imaging apparatus is provided with plural receiving coil units for receiving the magnetic resonance signals, the receiving coil units each comprising a coil body configured to receive a corresponding one of the magnetic resonance signals and output an electrical signal and an optical modulator configured to use an electric field of the electric signal outputted from the coil body directly as a modulation signal.