A measuring instrument and a measurement method which measures, using magnetic resonance, images such as a functional image, a morphologic image of an object to be measured eliminate the influences of the moving speed of the object to be measured during moving, thereby obtaining a precise measured image. The instrument comprises: the first and second external magnetic field generation devices (5, 6) which generate magnetic fields for exciting the magnetic resonance of a mouse (M) as a living body to be measured a turntable (8) which rotates and moves the mouse (M) as an object to be measured, thereby moving the mouse (M) in the magnetic fields of the first and second external magnetic field generation devices (5, 6) an OMRI measurement processing unit (31) and an MRI measurement processing unit (32) which obtain measured image signals within the mouse (M) by phase encoding while applying a gradient magnetic field in the moving direction (y) of the mouse (M) without stopping during the movement by the turntable (8) and a measured signal correction unit (33) which corrects the measured image signal (S (kx, ky)), thereby obtaining a corrected image signal (S(kx, ky)) wherein influence of movement in y-direction is corrected.
