An imaging mass spectrometer according to one aspect of the present invention includes an analysis executing section (1) configured to collect data by executing predetermined analysis on each of a plurality of micro regions set in a two-dimensional measurement region (50) on a sample (50) or a three-dimensional measurement region in the sample; a first image creating section (21) that uses the data obtained by the analysis executing section (1) to create one or a plurality of first distribution images each reflecting a distribution of one or a plurality of specific components included in the sample (50); a formula storage section (23) that stores, as a formula, a chemical reaction formula including at least the one or a plurality of specific components as elements, or a calculation formula including an amount of the specific component as element; a signal value calculating section (25) that calculates different signal values from the signal values in the micro regions constituting the one or the plurality of first distribution images by using the formula acquired from the formula storage section (23) in response to a user's instruction; and a second image creating section (26) that creates a second distribution image based on a calculation result.