PURPOSE: To shorten the image display processing time until a tomographic image is displayed after image data is reconstructed or an image processing is performed by providing an image memory device accessed by both a fast arithmetic unit and an image display controller.

CONSTITUTION: A magnetic resonance signal received from an object 2 is transferred to the fast arithmetic unit 13 as fundamental data for tomographic image reconstruction, and the fast arithmetic unit 13 A/D-converts the magnetic resonance signal, and reconstructs it to the tomographic image, and stores it in the image memory device 17, and transfers it to a CPU 11. Meanwhile, the image display controller 15 takes out the image data in the image memory device 17 by making access in sequence of the data whose reconstruction is completed, and displays it on a display device 20 as the tomographic image. Also, when the image processing for the tomographic image on the display device 20 is started up, the CPH 11 generates a processing start command at the fast arithmetic unit 13, and the fast arithmetic unit 13, after performing a designated image processing on the image data in the image memory device 17, transmits a processing completion command to the image display controller 15. The image display controller 15 displays the image data on the display device 20 as the tomographic image.