1. A sheet identification apparatus which identifies a type and truth/false of a sheet to be identified by comparing an image pattern acquired from the sheet with a preset reference pattern, comprising: area dividing means for dividing the image pattern acquired from the sheet into a plurality of areas, weighting means for weighting the areas divided by the area dividing means, area selecting means for selecting an area used for identification from the areas weighted by the weighting means, identification result acquiring means for acquiring a result of identification with the reference pattern for each area selected by the area selecting means, and identification result determining means for determining an identification result of a whole portion by a logical combination of the identification results for the respective areas acquired by the identification result acquiring means.