This incidence rate evaluation device is characterized in being provided with: a storage unit for storing diagnostic information, which stores regions of the body associated with differences between two images taken of the region at different times and with a disease name； and a control unit for receiving input of an image feature value category and the region to be diagnosed from a user, calculating the difference in the received category between the two images of the region that is being diagnosed in the patient and have been taken at different times, searching the diagnostic information using the region being diagnosed and the calculated difference as search keys, acquiring disease names of relevant records, calculating incidence rates on the basis of the percentages of the relevant records in the total number of records for the region, and displaying the calculated incidence rates for each acquired disease name.
