1. A magnetic resonance imaging apparatus comprising a measurement part for applying a radio frequency magnetic field and a gradient magnetic field to a subject placed in a static magnetic field and detecting magnetic resonance signals generated from the subject as complex signals, an operation part for performing an operation for the complex signals to generate an image, and a display processing part for displaying the generated image on a display device, wherein: the operation part comprises: an image reconstruction part for reconstructing a complex image in which pixel values are complex numbers from the complex signals, and an image conversion part for converting the complex image into a magnetic susceptibility-weighted image, and the image conversion part comprises: a complex image conversion part for generating an absolute image and a phase image from absolute value components and phase components of the complex numbers of pixels of the complex image, respectively, a magnetic field image generation part for generating a magnetic field image representing spatial distribution of magnetic field intensity from the phase image, a susceptibility map generation part for generating a susceptibility map from the magnetic field image, a weighting image generation part for generating a weighting image for performing weighting for emphasizing contrast difference of a tissue of interest and a surrounding tissue from the susceptibility map, and a magnetic susceptibility-weighted image generation part for generating a magnetic susceptibility-weighted image by multiplication of the absolute image and the weighting image.