An imaging mass analysis data processing method of processing imaging mass analysis data in which mass spectrum data collected by performing a mass analysis on each of a plurality of measurement points on a sample is associated with spatial position information of the measurement point, comprising: a) a spatial point interval equalization step in which a spatial measurement point interval in one of a plurality of imaging mass analysis data is defined as a reference, and mass spectrum data at each of virtual measurement point positions in another imaging mass analysis data of said plurality of imaging mass analysis data is obtained through interpolation or extrapolation using mass spectrum data at a plurality of measurement points around a respective virtual measurement point position, the virtual measurement point positions being virtual positions in the other imaging mass analysis data obtained by equalizing an actual measurement point interval in the other imaging mass analysis data to an actual measurement point interval in said one imaging mass analysis data defined as the reference; b) a mass-to-charge ratio equalization step in which a mass-to-charge ratio range common to mass spectra in the plurality of imaging mass analysis data is extracted, mass-to-charge ratio points within the extracted common mass-to-charge ratio range in one of the plurality of imaging mass analysis data are defined as references, and an intensity value at each of virtual mass-to-charge ratio points in the other imaging mass analysis data is obtained through interpolation or extrapolation using intensity values at actually measured mass-to-charge ratio points lower and higher than a respective virtual mass-to-charge ratio point, the virtual mass-to-charge ratio points in the other imaging mass analysis data being mass-to-charge ratio points obtained by equalizing actually measured mass-to-charge ratio points in the other imaging mass analysis data to actually measured mass-to-charge ratio points within the extracted common mass-to-charge ratio range in said one imaging mass analysis data defined as the references; and c) a combining step, in which the plurality of imaging mass analysis data in which the measurement point intervals and the mass-to-charge ratio points are equalized by performing the spatial point interval equalization step and the mass-to-charge ratio equalization step are combined so as to be treatable as one imaging mass analysis data. a) a spatial point interval equalization step in which a spatial measurement point interval in one of a plurality of imaging mass analysis data is defined as a reference, and mass spectrum data at each of virtual measurement point positions in another imaging mass analysis data of said plurality of imaging mass analysis data is obtained through interpolation or extrapolation using mass spectrum data at a plurality of measurement points around a respective virtual measurement point position, the virtual measurement point positions being virtual positions in the other imaging mass analysis data obtained by equalizing an actual measurement point interval in the other imaging mass analysis data to an actual measurement point interval in said one imaging mass analysis data defined as the reference; b) a mass-to-charge ratio equalization step in which a mass-to-charge ratio range common to mass spectra in the plurality of imaging mass analysis data is extracted, mass-to-charge ratio points within the extracted common mass-to-charge ratio range in one of the plurality of imaging mass analysis data are defined as references, and an intensity value at each of virtual mass-to-charge ratio points in the other imaging mass analysis data is obtained through interpolation or extrapolation using intensity values at actually measured mass-to-charge ratio points lower and higher than a respective virtual mass-to-charge ratio point, the virtual mass-to-charge ratio points in the other imaging mass analysis data being mass-to-charge ratio points obtained by equalizing actually measured mass-to-charge ratio points in the other imaging mass analysis data to actually measured mass-to-charge ratio points within the extracted common mass-to-charge ratio range in said one imaging mass analysis data defined as the references; and c) a combining step, in which the plurality of imaging mass analysis data in which the measurement point intervals and the mass-to-charge ratio points are equalized by performing the spatial point interval equalization step and the mass-to-charge ratio equalization step are combined so as to be treatable as one imaging mass analysis data.