In a method and system for determining an optimal MRI scan nesting manner, selectable nesting manners are determined according to a preset number of simulated scan slices; one nesting manner from all the selectable nesting manners is sequentially selected; based on the selected nesting manner, a simulated MRI scan is performed using a preset pulse sequence, and a longitudinal magnetization strength after relaxation of each slice when scanning ends is calculated; when all nesting manners have been selected, based on the longitudinal magnetization strength after relaxation of each slice when scanning ends corresponding to each nesting manner, a nesting manner for which the longitudinal magnetization strength after relaxation is smoothest is selected, and the nesting manner is used as an optimal nesting manner for performing an MRI scan of the tissue.