To provide a gradient magnetic field coil device capable of realizing high gradient magnetic field strength and the quick rise of a gradient magnetic field even by the power source of a relatively low voltage, light in weight and easy to handle.

A gradient magnetic field coil for the whole body in which X, Y and Z coil sets are combined is composed of a main coil 41 and an active shield coil. The gradient magnetic field coil for a local area is also composed of the main coil 47 and the active shield coil 43. Then, the active shield coil 43 is integrated with the gradient magnetic field coil for the whole body and formed fixedly in a gantry and only the main coil 47 is separated and made attachable and detachable to/from the active shield coil 43. The main coil 47 is mounted at the time of local area photographing and the main coil 47 is detached at the time of whole body photographing.