1. A magnetic resonance imaging (MRI) system comprising: exciting means for magnetically exciting a plurality of regions of an object using a multi-slice MRI process, the plurality of regions being located within a predetermined imaging range provided by the magnetic resonance imaging system and a first region being excited at intervals a plurality of times while in the predetermined imaging range such that at least one other region is also excited during a period between said intervals, wherein the exciting means includes position-moving means for moving spatial positions of the plurality of exciting regions synchronously with movement of the object; acquiring means for acquiring MRI multi-slice echo data from the plurality of excited regions of the object while the object is continuously moved; and processing means for producing image data from the echo data acquired by the acquiring means; wherein the plurality of regions include multi-slices of the object; wherein a slice-selective axis direction of the multi-slices used in the multi-slice imaging process corresponds to a moving direction of the object, and wherein the exciting means includes means for adding another slice to a tail of the multi-slices as a slice belonging to the plurality of multi-slices in the moving direction in cases when a head slice of the multi-slices in the moving direction goes beyond the imaging range.