A magnetic resonance imaging apparatus includes: a pair of static magnetic field generators separately disposed at the top and bottom of an imaging space in which a subject is placed a shim magnetic material, disposed on the imaging-space side of each of the pair of static magnetic field generators, for generating a magnetic field to adjust the static magnetic field a gradient magnetic field generator a high-frequency magnetic field generator a temperature sensor for directly or indirectly measuring the temperature of the shim magnetic material and a controller for controlling the gradient magnetic field generator and the high-frequency magnetic field generator to execute an imaging pulse sequence. The controller determines the inhomogeneity of the static magnetic field from the output of the temperature sensor, considering the change in a magnetic field adjustment parameter due to the temperature change of the shim magnetic material, and causes a warning message to be presented if the determined static magnetic field inhomogeneity has exceeded a predetermined allowable value.